I kissed a girl that has a boyfriend and messed around a bit but didn't go further because I felt guilty for hurting their relationship. Its never going to happen again but I can't help but feel guilty and bad. Has this this happened to anyone else and should I feel bad?

It's a good thing that you feel bad. It's called conviction. It is very wrong to mess around with a girl that is taken, the last thing you want is something like this on your track record. You don't want to tell your future girlfriend/wife that you kissed and fooled around with a girl behind her boyfriend's back. Not a good idea. This kind of guilt is a good thing, because what you did WAS wrong. Make sure you learn from your mistake, and don't do it again. It may not seem like it, but it's actually a good thing that you feel this way.

Yea, you should feel bad. You're not acting with integrity if you fool around with someone else's BF.

Try and imagine it being you. How would you feel if someone was fooling around with your BF? Not happy, I bet.

In any case, he's a jerk for cheating on her with you.

It's good to review your behavior and ask yourself if what you were doing was right or wrong. Next time, I know you'll think twice.

In this situation, you knew it was wrong, you did it anyway, you now feel guilt and remorse.

Good for you. Pay attention. Guilt is a learning tool. Learn from what it is teaching you. Do not let your mind ignore it, rationalize in any way.

Guilt is all about improving FUTURE behavior. If you do not improve, then you're feeling all this angst for nothing, how awful would that be!

Make sure you benefit from this.

The past is the past.

Lesson learned. Don't do it again.

I think its good you feel guilty to! A few years a go I messed around with a guy and later found out that he was in a relationship.. that made me feel REALLY bad! Of course I didn't know. But it didn't make me feel any better about it and I def. felt even worse when the though struck me: how would I feel if my BF did that to me... :/

I do think of it as a way to learn, but also a sign of actually owning some integrety and a conscience... so feeling bad about this is a good thing!!

note: that is not to say that you should beat yourself up about it forever though!! But def. learn from it!!