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I think my boyfriend is cheating on me with my sister!!!!

Me and my boyfriend have been together for 2 years. Recently I have suspected that he is cheating on me and worst of all with my sister who is 1 year... Show More

I know it's been a while since I have responded to your answers I am sorry I have had so much going on. But since then a lot has happened and unfortunately you were all right. The lying and low life EX boyfriend now did cheat on me and YES it was with -->
so called SISTER...And NO they didn't have the decency to be upfront and tell me! My suspicions were confirmed as I saw sick text messages from one another on my so called SISTERS Mobile phone..I still feel hurt and betrayed!
I also would like to say a HUGE thank you to everyone who answered and commented I did read your all your answers at the time they were posted but it wasn't until I found out about 2 weeks ago that I had the courage and energy to respond and update-->
as I am still very hurt. It's nice to know there is still good people out there who can take the time to respond to a strangers cry for help..Thank you all any further questions you have don't hesitate to ask.. :)

Most Helpful Opinion

  • I assume you live with your sister? Next time they're both 'working overtime,' go to her workplace. One of 3 things will happen:

    1) She's there. In which case, your boyfriend probably isn't cheating on you with her. Just say you're glad you found her because you've locked yourself out and don't have your phone/the battery's dead, you just went out to call the cat/get the milk/whatever and the door shut behind you. Take her keys and go home. Call your boyfriend's workplace and ask to speak to him quickly. If he's not there, he may still be cheating but with someone else - that's a whole other story. If he is there, just ask him a random question that he would know but you wouldn't or could have forgotten ('I've got this homework and I can't remember what the answer was'/'I forgot the password to my computer! What was it?'/'I'm on the internet looking for a birthday present for my dad - you're a guy, what d'you think he'd want?') and be done with it. So they're probably not cheating, but you do have some issues to work through and talk about. Separate story.

    2) She's not working late today, or not at all. Tell her colleagues you just came by because she owes you some money and you wanted to buy something (left your credit card at home, short on cash and wanted her to repay it, whatever. Plus siblings always conveniently remember and forget about money owed so it doesn't really have to be true), but it's okay, you'll just ask her when she gets home and buy that thing tomorrow. Step outside, call your boyfriend's workplace and try that question thing. If he's there, then it's a bit weird that your sister isn't at work but I guess the point here is that he is. Either try a similar thing again in a little while to settle it, or just work through the stuff with your guy and ask your sister why she lied about being at work - say you were worried, as her older sister, etc.

    3) Neither of them are at work. Worst case scenario. Swing by his place, or get someone you really trust to do it for you. How old is everyone involved? If he lives with his parents, you could try calling them and asking if he's home (if they ask why, it's because you forgot the password etc) or if he's by himself, you'll have to go over there. You can hang outside a window and see if you can see/hear anything but that could be really disturbing if you do. You could just ring the bell but they might see it's you and hide or something. That's where someone else comes in handy. If you want to be really sneaky, sit outside the house somewhere they won't see you (on his neighbour's wall?) and order a pizza to the house in your sister's name. Sit and wait. they might come out of the house, in which case you've caught them. If not, the pizza comes and your sister opens the door - again, you've caught them. Or your boyfriend opens the door and the pizza guy says he has a pizza for [your sister]. Your boyfriend calls her from the other room to ask when she ordered it, and you've got them.

    • If neither of them are there, and they're not at work, they're probably out somewhere. I'd bluff to your boyfriend and say you know they're cheating and someone saw them out together. He might crumble and admit it or seem nervous - that's proof. If he actually has a valid alibi, then what the hell was he doing? Why has he been so distant lately? Why does he always compare you to your sister etc.

      I don't have a sister but I guess it does happen. I hope you figure this out. Good luck! x

    • Show Older
    • I know now I saw the text on my so called sisters phone...We don't talk anymore and they are still together..I don't know who hurt me more him or he..I think it's her my own blood! How could she do this to me, I did everything for her as a sister and I loved her and would do anything for her. She had to throw it all away by going after him! :(

    • That really sucks... sorry you had to go through that =[ get away from them, at least for a little while. Hang out with a close friend or other family, meet other guys, whatever. That was really low of them and you don't need to put up with it. Hope you feel better soon x

What Guys Said 20

  • Sure sounds like she is. This is more common than people think. Siblings have a lot of time to spend with their brother or sister's significant other and know a lot about their sibling's past...

    I"d confront her and him about it right now! The longer it goes on the worse you will all feel.

  • Wow, I'm guessing it's time to dump him. And for your sister, hopefully you two can work it out. But she's not to be trusted, ever again.

  • It is possible he is cheating on you with her, but doesn't mean he is, the thing is you have to find a way to catch them, because if they are doing this, there is no way in hell they will tell you, and will do anything and say anything to get out of it. You could corner either your sister or your boyfriend and be like well the other one admitted to what you guys are doing! what the f*** and see if one of them breaks, and if they deny it, be like if to your bf, well we are done either way so you might as well tell me the truth. granted if you say that then you are saying you are ending it. It would be easier to get your boyfriend I think, because you could say. My sister told me everything you guys have done, and she said she can't keep it from me any longer. These are just suggestions, not saying you should do this and saying you shouldnt do this. Its up to you.

    Whenever you figure out the truth in the end, fill us in =]

    • All updates are now available..

    • I see that, that's f***ed up. regardless of who is more attractive, you don't leave one sibling for the other, and its f***ed up when a friend goes behind your back and does this, but your own flesh and blood.. come on now. I've seen relationships where the first sister cheated on her ex for another guy, and her sister ended up taking her ex. in this case I think that is fine, the first girl doesn't deserve it. but in your case.... wow is all I have to say on both your EX and your sisters part.

  • It's just sad you actually waited for him to CHEAT on you before breaking up with him. -_-

    • Your right I am! This is my issue I like to think the best of everyone, I should have known better.

    • Don't beat yourself up over it - just keep it in mind for next time. It sucks big time (and I'm about to sound like some kind of cheesy ancient proverb haha) but sometimes the worst heartbreaks are what teach us the most important things about our best future relationships. I speak from experience =] what you learn about yourself and how to handle those around you can really give you amazing experiences later on.

  • If I were you, I would leave your boyfriend and never trust your sister again.

  • Hmm sorry to hear you had to go through all of this. You are definately the better person. Things have remained unchanged? Still no remorse from your sister either?

    • Thank you. We still don't talk, and don't attend family stuff if we know each other will be there, Very sad though. I miss her in a funny way, I know it's weird. As far as I know they are still together and live together as well.

    • No its not weird at all. But in what every way possible I hope things can get better for you. And hopefully one day you will get that well deserved appology from both of them.

  • I am so sorry,I am just checking back with your update.Heart break sucks.

    • Thank you :) I'm getting through it day by day..

  • First off holy sh*t.This does not really surprise me,check this out.Overtime at work on the same days,comparing,smiling and giving eyes,no sex in 2 months,they both hide phones? Ok,either they are planing a surprise party for you,they are the worlds greatest lie,they are just really that close and its harmless,or am sorry cause its you sister but somebody seem like a slut.No sex part is really getting to cause usually a guy would say this about his girl not the other way around,you should be scared.The only thing I can say get a Pi and see what is really going on.

  • Wow, your sis must be hot. Look just sneak into her room when she's sleep and grab the phone

    Your Boyfriend is doing this for a reason...maybe you've gained weight? Maybe you don't dress as nice as you used to? Point is he didn't do it just for the hell of it. You must be doing something wrong

    • You serious!!?? if she's doing something wrong then dump her don't go after her sister come on that's just f***ed up!

    • Show Older
    • Its a guy fantasy to do sisters lol. maybe that's why

    • Sorry that's a total lie! Girls/Guys please give your opinions on that last statement.

  • NO SEX FOR TWO MONTHS :-D beat the crap out of your sis to spit it out . she has to tell you if its your boy friend she is talking to . but you do have friends who are guys that are potential treats to him. just talk dirty with one of when his around . or tell him your spending the afternoon at their place . if he panics or get extremely jealous then I think he stills loves you . but if he play the I thrust you bullsh*t when you people have not had sex for TWO FRIGGING MONTHS ! then he having an affair. either way to me DUMP his ass and get some one who can give some good pleasure 24/7 for 12 moths non stop . when you stop having sex then the love is over

  • well my god honest answer with past experiance is that he is cheating on you with our sister. my past exp. was that this happened to my cousin 2 already and she got very depressed and really beat herself down for this happening so please don't let this hapen to you and ifyou still think he's not and your curious hire a pvt investigator!

    • No need now I know the truth..

  • So sorry to hear you were right, but people usually are when everything inside tells them something is up.

    Don't beat yourself up over this though, look on the bright side. I know it doesn't seem like there can be a bright side, but there ALWAYS is. You're between 18 and 24 and you've learned that you were dating an asshole. Now, before you commit some of the best years of your life (20-35) to him, you've learned that he isn't worthy and you can find someone else to share your best moments with. And your sister will get hers in the end - for starters it turns out she's dating a cheater and if she thinks she'll be the one to change him then she'll soon be the one feeling broken and by then she may just end up coming to you for comfort.

    Remember, better today while you're young than in a few years after you're married with kids.

  • whats up with a depression sh*t? don't let nobody make you feel that way. if what you assume is true then there is always a thing called karma. those muhfukas gonna get some troubles later. and you gotta talk to both of them because that ain't cool. thank god I'm an only child

  • Unfortunately, your boyfriend IS cheating on you with your sister. Your sister is wrong as hell. You need to get that piece of trash (ur bf) out of your life. He's hurting you... get rid of him, and kick your sister's ass.

  • yeah I'm sorry its happening you should sit them down an ask them because your gonna get hurt so have them apologize and if you interested later on I can hook you up with a real man pick one off this video k but other then that enjoy this an smile because you deserve it link

    • Aww your really sweet :) thank you!

  • Let's face it, this is every man's fantasy. Well, either sister or best friend. They just won't admit it because of social conventions.

    You should steal his phone. Or hers. Or think of some way to make them give it to you and then run away.

    Or you could follow them when they're supposedly working overtime.

    • No more suspicions..Facts now :(

  • Well you don't have any real proof of them actually cheating and doing stuff etc, he might like her more than he likes you maybe just cut him lose and let them be happy or miserable together, mabye you could hook up with his brother if he has one or his dad ...

  • It seems that your boyfriend is cheating there are 90% chances but you don't have solid proof so first get solid proof then decide that what should do? Try to catch them together and if you get solid proof about cheating then leave your boyfriend.

    • 100% now..

  • it does sound like that might be what's happening.


    you should drop him or at least confront him about it.

    i mean you should ask your sister what's really happening.

    good luck

  • forget about him you need a good guy I your life

What Girls Said 26

  • i would distance myself from the so called sister. she's crossed a line that can never be erased in my eyes and I'd consider the honesty and trust void as of that. that really sucks and I hope you have friends that are close that you can talk about or confide in or just hang out with to take your mind off of it. your so called boyfriend turned out to be a jerk so get a better boyfriend. I'd feel hurt as well if I were in your situation. there's no easy answer. if I were there, I'd just cut ties with the sister.

    • It's really hard for me I don't talk to my sister anymore I havnt heard or spoke to her since. The worst thing is she didn't have any remorce for what she did. Like I always say I hope he is worth it because she has lost a sister for life and if he did it to me he will do it to her to. Then who will she have no one.

  • Did either one of them say how or why it happened?

    A sibling is probably the worst person that could possibly do that to you. I'm SO sorry for what you've gone through. I wish you the best.

  • I understand that you hurt, but at least you know the truth. Now you can find a real man.

  • F*** THAT. You need to confront both of them girl. Don't take that sh*t. You only live once; you need to know the truth. If your having that gut feeling girl you might just need to end it and if he is f***ing your sister; SLAP THE SHIT OUT OF HER. SIT THEM BOTH DOWN AND FIND OUT ANSWER! Please don't let them take advantage of you like that. FIND OUT THE TRUTH! You have every right to know. Honestly if you guys haven't had sex in 2 month; something might be going on. Even if you suspect; you still have a right to sit both of them down and tell them how you feel. Be real about it; your a grown mature girl and you have the right to know. You only live once; find out now what is going on! If they are doing that behind your back you need to tell them both that they sick and you will never have respect for either of them or trust. Sorry; sister or not; you treat people the way you wanna be treated.

    • AMEN GIRL!!!!!

  • I would go for the sister first. Get her phone while she is away and if she catches you with it say you can't get reception or something. I would say your boy is cheating on you with your sis. If I were you and I am not a violent person at all, I would put her in her place and just beat the wholly sh*t out of the slut. Tell her how low and revolting she is. Then call up the boy one her phone and tell him you know then go after him and just unload on him. Then I would tell your parents just to show then ho slutty and disappointing their daughter is. I have sisters and if that ever happened I would be out for the kill. He is most likely cheating on you. I am so sorry. But before you jump to conclusions ask him vague questions like my sis told me what you've been doing. Or better yet catch them in the act. But whatever you do don't ask them outright. They will not admit it.

  • Wow this is crazy. I would for one spy on her and make sure she does not find out! You pretty much need prove before you can say he is cheating. Don't sit down and talk to your boyfriend about it because he might lie to you and same goes with your sister. She is a backstabber. Before you go off guessing get the facts and evidence first. Then you can go out with his best friend or his brother if he has one his age. Or better yet move on and forget the bastard. Something tells me you did something to make him lose interest in you. I could be wrong. You deserve better. Listen to this song: Taylor Swift- Picture to Burn. I think the lyrics are great regarding your situation.

  • Awww I'm so sorry to hear that, he wasn't right for you, the right guy won't do that to you.

    I hope you're coping well.

  • I empathize with you, you sound like a very nice decent young lady.

    I am happy that you dumped the a**hole!

    As for your sister, do not trust her again. Personally, I wouldn't even call her 'sister' anymore.

    Good luck, and don't despair! A good man is out there for you, within your reach!

    • Thank you very much :), I hope so too...Your right I don't even consider her my sister anymore.

  • Honey I want you to do something you have never done before... when your sister is on the phone.. grab it and check whos she's talking to ... hit redial if need be.. and if she is talking to your boyfriend then your next step is a good slap.. Boys come and go.. sister are for life.

  • I am sorry to tell you girl but, they are doing each other big time behind your back. If I was in your situation I wouldn't come out and tell them you know because, they won't last but, your sister will still be around after this hole thing blows over. I am not saying it is going to blow over fast it mite take a while. I would make up some reason to break up with him and then go on about your life. You are way to good for a guy like that. Sorry to say that about him but, I think it is true.

    Good Luck,


  • that asshole talk to your sister ask her honestly what is happening if she won't tell you go to your boyfriend dump him then tell your sister that and see what her reaction is

    Good plan huh wow sometimes these things just come to me hahahaha


  • here is what you do call cheaters the TV show MUHAHAHAHAHA or hurt your sis untill she spills it same for him HAHAHAHA EVIL!...sorry bout that iv been up for a long time

  • Break up with him and slap the sh*t out of your sis, that's what I would do

  • This is def something you need to ask him about. Just tell him that he needs to stop making flirty faces to your sister and stuff, then if you keep telling him stuuf like that he should fess up soon.

  • WOW, Do not let anyone make you feel horrible for something you didn't do. Any man that compares his girlfriend openly with other girls, is not worth a girls time.

    My sisters husband said that if he wasn't married to her he would date me. I wondered why my sister was giving me the ugly eye. When she told me, I chewed him out in front of our family. If he was going to under mind my sisters self respect/worth as his wife he wasn't going to be welcomed in my home as my brother-in-law.

    Heres what you do take off, go do something fun and exciting for your self. Build your self respect and confidence again. Key don't tell either one of them. Confronting them may fuel something you aren't ready to be faced with if you are feeling depressed. You need to be strong and level headed about what direction you want to go when you find out the truth.

  • 2 months without sex! He's definitely cheating!

    Leave him and beat your sisters ass! That's disgusting!

  • aw sweetie. ask him or get her or his phone when they are asleep. good luck.

  • Talk with them! Both! Tell them what's going on between them.

    And the next time you're with your boyfriend, ask him if you could see his phone. If he doesn't let you, ask him why. Try to make him spill the secret he's been hiding.

    For your sister, just try to get her phone without her suspecting it. Act normal around her and don't act suspicious. But be as cautious!

    If you can't do these, I don't know. I just think there's something going on between him and your sister. If you still suspect that you're boyfriend is cheating on you, dump him! He shouldn't be cheating on his girlfriend with his girlfriend's little sister. That's all sh*t that he's doing right now.

  • Aww,i'm sorry,no one deserves to have this happen to them.

    It sounds like he is cheating with her.Confront them:)))You truly do need to confront them

  • im sorry this is all happening to you :( but I would say you need hard proof. and unless you don't find them in bed together or anything like that you can't accuse them. However the way he treats you tells me he's an ass and that you should dump him anyways. And it also depends. Are you bugging him about everything that he's doing? not justifying him or anything. But if you are, then he's gonna act like that. The best way to get back at him would be to pretend you don't care. What you need to do right now is act independent. Go out with your friends, maybe work out extra hard and tone up? or lose the extra pounds. There's no greater revenge then to look good. Trust me. And if you find that he starts being nicer to you because of this, dump him. Trust me, it's worth it.

  • Eww. that is so sick! First off your sister needs a sisterly love bitch slap! Leave your boyfriend and find a guy that won't f your sister!

  • Yep, sounds like he's cheating with her. If I were you, I would end it with him, and then end my relationship with her to because no sister should do that. But first, you should get the facts and find out if it really is happening or if it's all in your head. confront him and her about it and see what happens. That really sucks if it's true. I hope I helped.

    • I'm glad you said get the facts right first.

    • You are right about her getting the facts straight. But usually in a situation like this where she said "He also comments on how I should be more like her and compares me to her a lot when we fight." That is ALWAYS a very strong indication that he is cheating on her. A real boyfriend would never compare the woman he is dating and cares for to another women. That right there would lower her self esteem. It also shows what he is thinking. If he is always comparing her to her sister

    • Then he is seeing flaws in her that he does not see in her sister. Which is very bad. It means that he has feelings for some one else and is losing feelings for her. I am very sorry to say this but it is the truth. You already know the truth your self, you gut feeling is telling you that he is cheating. In the end our gut feeling is usually right.... It is all up to her what she will do from here out...

  • talk to your sister about it.

    She should be your bestfriend.

  • dump him. he shouldnt be treating you like this and you deserve better

    you need to check your sister. do you think she would ever do anything like this? but if she does something that's inappropriate you need to let her know. ask her wtf her problem is and tell her to stay away from your man. I have a sister who is much younger than me, but if I had one that was old enough to date and she did this to me I would beat her ass real talk, maybe that's what you should do

  • Trust him until you actually have proof. When you suspect you take every little thing to mean something bad. Ever thought of asking him? or talking to you sister? If you have been in a relationship for two years doesn't that mean that you can talk to him about anything? If its true than I am really sorry but I hope it won't be

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