Puts you in a hard place..I would feel conviction to let the fiance know.

i'd confront her.

just tell her what you think, sometimes people like that just need kind words and a reality check

The only issue with that is that me and her dont get along at all... It makes it even more akward, you know?

My first roommate cheated on her boyfriend all the time. I said nothing. Until one day, years later, she tried to seduce MY fiance.
My opinion--you should confront her ASAP.

Okay, it was really hard to do and we dont talk but I IMed her and she hasn't responded... she probably won't haha

Please, let her be the one to come clean. Just keep telling her you aren't comfortable with this knowledge and if she doesn't come clean, you are going to have to because it's eating you alive. This happened to me and I knew I was wrong to burden her (she was my best friend after all). I just wish she had come to me first before blowing our lives out of the water (although I know that it was I who did that, I was trying to find a way to tell..I hadn't gotten there yet, unfortunately).

it's hard to get close to other women, we all know ourselves how we can be catty.

def. don't tell her fiance about this, it is between those two. just try to confront her. all you can do is try, right? that's it.

You should tell her fiance. He doesn't deserve this. You may be able to stop him from getting an STD too. Tell him before it's too late. Be prepared for her to deny it though. Good luck!

Well, I've disliked her for a number of reasons from that start, and I kicked her out of the apartment (she leaves tomorrow)- I let her know I will tell him if she doesnt, so I think I'll message him this weekend.

I would tell/confront whomever you have the most loyalty to. I knew a couple. I used to work with the wife, then her husband got me a job where he works. So I became friends with both. Rumor mill said he was cheating, so I told her. For whatever reason, she didn't want to do anything with that information. But at least I felt I did the right thing.

My God! NO! Don't get involved with that. It is not your business to be involved in their relationship. How close are you to the fiance? Unless the two of you are very close friends or related stay out of it. You think you and your roomate don't get along now, wait tell you break the secret.......It's lible to get you hurt...Emotionally or even physically.
Distance yourself from them as much as possible. He will find out eventually.

I would suggest that you talk to her and see why she feels compelled to cheat on him. Maybe suggest to her if she is not happy why not leave him instead of stringing him alone. Considering that the two of live together I would assume you have a close relationship if so use that to tell her how you feel about the whole situation, maybe she will understand and respect your opinion enough to take your advice. I

Always remember that whatever you do will always come back to you. It is not your place to say. The only reason why you want to say something in the first place is to be bitchy because you don't like her. Just stay out of it, you don't know what she would do if she knew. I agree with Jayba--it might just be for your own safety

I would tell the guy... How would you like to be engaged to someone who's out boning someone else. I think that's pathetic.

Let the guy know. You'll be doing him a favor long term.

Thanks Ted... as for Jayba and katamaz, well, you just inspired to tell him because first of all, America has a stick up its ass, because here we dont get involved in people's business which isnt really a good thing all the time. also, the LAST thing im afraid of is being hurt by her- she's way to lazy to do anything about it and besides "i could take her"...easily :) also, jayba, he's never gonna find out: he's a really sweet guy, but not the brightest crayon in the box...