My ex boyfriend is hanging out with his ex before me?

I'm not really sure what's going on here. You guys broke up and you're getting upset with who he sees? You're not going to like this, but given how you've described things it does sound like he's going to the event to maybe rekindle something with her or meet new people. This all depends on how long things have been going on though. If they had dated for awhile and he hooked up with you after 3 months, well, I'm sorry but that isn't very long. But in either case, you should get over him. I know right now you're hurting, but even if you got back together there would still be friction with your past and that girl. You'd be worse off then than you are now. I'd suggest stop snooping around on his Facebook and stop talking to him and trying to find out what he's up to. Do your own thing for a little bit and you'll meet new people. You don't deserve to be this hurt over a guy. It's his loss.

Its possible, but it could also be that they got along really well so maybe she is like a safety net or something? Jealousy can push you apart because you don't act like yourself, but it can also be attractive if it is not consuming you. If you want him back you should talk to him ask him what is up. You didn't mention who made the brake up I am guessing it was him, If it was he might of realized he still had feelings for her... but I don't have much info on this situation so the best thing would to just call him up or something and tell hm why you want to get back together.

Quit stalking who cares that they are going to the same event. I don't know why he broke up with you, but If he has broken up with you "officially" like he told you to your face he can have passionate sex with her and he wouldn't be doing anything that's wrong or your business.

welldone , you took a brave step

either he's doing it to get your attention or its because he still has feelings for her ... but sorry to be harsh if he's being pushed away by your jealousy I think he's truly into the other girl... who broke up with who? and for what reason would help to answer better.

you are hung up on him. you need to get over him he's well over you. its time you find a guy and start dating around untill you move on. the best thing you can do is to get over him and enjoy your life free from him..

why even bother to check his Facebook? find somthing else to do.

A few things.
What type of event, how close is he to the ex (ie friends for years before you), is their mutual friends at the event, can you go to the event, has he told you he is going to this event or have you asked him, without logging on to his Facebook to snoop are you aware of this event or can you sign into your face book and find the event mentioned on his Facebook profile so you can ask him about it?
Too many questions, too much vagueness, do I picture you as a psychotic woman making this poor guys life hell with his ex being a shy girl scared of you or are you some woman who is fed up with mr machismo known for cheating and lying meeting up with some nasty cow who would stop at nothing to take advantage of your mans inability to say no.
The difference in the two affects the answers you will receive.

First off, once he becomes your EX you have no say in what he does anymore. Period.

Even if you were still dating, this would be a bit of an overreaction. It's not like he's going out to see her - it sounds like they just happened to be invited to the same event (I take it you all have mutual friends).

In any respect, you obviously still have feelings for him, so you're naturally going to react to stuff like this the way you are. Sooooo...

Just ignore what's going on in his life and start moving on with yours. Don't drive yourself crazy and give Facebook a rest for a bit...

First of all he's your ex now so he can do whatever he want. If he wants to waste his life with that girl so be it.

Second, delete your Facebook. Facebook = drama = ruined relationships.

I don't know about you, but I don't usually even end up going to half of the events I RSVP for on FaceBook. I'm not flaky like that, but I find RSVP's a good way to spread the word for an event I support without having to attend if I can't make it.

Is he like that?

Heres an idea- grow up, get rid of your Facebook (it's destroying everything) and think about what his motives are. Two girls, who he's had each of, in the same location. It's a p*ssing contest.

that is messed up hun...happy you're moving on

I think that you're over reacting, has he ever given you a reason not to trust him? In my opinion if you can't trust the guy you shouldn't be with him. And if you guys all live in the same area, then why get upset that they could possibly bump into each other? It's your insecurities that's making you over react about a little thing. But like I said if you can't trust him, don't follow through with your relationship because a relationship is based on trust.. Has he been acting differently at all? And did you even ask him if anything was going on, before tripping out?