My girlfriend and I have had a serious relationship for about 18 months now. When we first started dating I found out about a guys she was seeing on the side from a past relationship. It was tough, but she talked me into staying together and promised there would be no more of that. We never really had a real strong relationship after that, because I have always had it in the back of my mind that a tiger can't change it's stripes. Recently I was called away on business, and just found out that she is back with the same guy while I am out of town. I know I have to now leave this girl, but I found out about the guy in a very unorthodox way, almost invading her privacy because my curiosity was overwelming. The problem is I don't know how to break it off with this girl without revealing how I found out. I am also to angry to break it off like it was my fault, but her first question will definatly be, How did you know? any help?
