I've made a big mistake and got drunk and had sex with another girl and now she found out and I don't know what to do. She wants to break up with me but I love her and told her it was a mistake. I wish I didn't do this but I did. I can't turn back time and undo this. What do I do? I love her and don't want to lose her. I would do anything to make it up somehow. How do I regain her trust after this huge mistake? Any advice is greatly appreciated!