my friend told me that my girlfriend is cheating on me, that she tried to get with him and that she is having sex with someone else but he won't tell me who. i told her someone had told me she was cheating but she won't admit anything. she kissed another guy a few months ago but she admitted it to me after the other guy told me and she said it was a mistake and it wouldn't happen again. i don't want to believe it but my friend told me he knows its true and hes never given me a reason to not believe him about something. what can i do if she won't admit it, i'm not sure i can end our relationship without knowing for myself. our relationship is really serious and we were going to get married not long from now. i care a lot about her but i don't know what to do about this. i have to know the truth about what has happened because if she hasn't had sex with anyone else but has done other things then it will be really hard and i couldn't marry her so soon, but i may be able to get past it with her eventually, but if she has had sex with someone else then it takes away how special it is when we are together. plz help. thanks.
