SadJeff, when I found out my H was "dating" someone my heart just about broke, I demanded that they end it, he claimed they did but he just hid it better. This went on for months. When someone is cheating, you can not believe a word he/she is saying, she is not herself, and is not thinking rationally. The best thing to do is stay out of her way and be the best version of yourself that you can be, take care of yourself, keep your mouth shut, and observe what is really going on. This is the hardest thing in the entire world to do. But this is what you are facing right now.
You are in a good place, you will get great advice. Keep posting, keep reading, take care of your basic needs now- sleep, eat, don't isolate yourself, get some exercise. There is no easy fix, you are in for a long haul, so start with the basics. I am sorry you are in this situation.
