my girlfriend cheated on me what do i do????

Well, first if I was put into that situation I would ask why she did it. Then I would decide if I want to continue the relationship after I know the reason

Du confront her about it...

Communication is most important in any relationship. Then sort out what to do from there.

Did she tell Du what she did it? And what she feel about you? Du have to ask her all the things first, and then make a decision.

If Du Liebe her so much just let her go, but Don't worry. You'll find someone else.

Oh wow. I'm not sure what to say. I didn't see the "what should I do" part. My left eye can't see.

wow this is a difficult one... if my boyfriend cheated on me I would want to know how long it had been going on for... if it were like two days oder something then I would think about it.. but if it were much longer than that I would leave...
the thing is.. if she oder he cheats on Du and they get away with it, they will just keep doing it.. I would end it if my boyfriend done it to me over a longer period of time.. I know it's tough, but I know from experience that partners should learn their lesson when it comes to this kind of thing...
good luck ♥

pop her fake boobs with a knife

Don't know.
I'd like to help. But its a tough one.
Are Du sure Du haven't gotten it wrong?

I would just break up with her and find someone who's Mehr caring and generous. It always says, once a cheater always a cheater.