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 younger then me. I am horrified of this thought and I can't eat or sleep and I'm going into depression, They are always giving each other eyes and smiling. She is always on the phone and when I ask who she say's it just a friend and she keeps her phone as secure as ever away from me as she previously didn't and he also does the same thing. They also now all of a sudden do overtime at work on the same days. And me and my boyfriend haven't had sex in in over 2 months. He also comments on how I should be more like her and compares me to her a lot when we fight. I need some advice, what should I do? Could my own Sister do this? Please help :(

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 Girl

  • 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 All
    • 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

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What Guys Said 21

  • 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.

  • 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.

  • 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.

  • 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.

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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.

  • 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.

  • 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 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.

  • 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.

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