How would a married man feel if he hasn't talked 2 his ex mistress since he got caught cheating 4 mths ago but now she makes the first move to talk to him again when they were friends b4 the affair?

He would lay low for a while. It is hard to end a relationship that has history. (The kind he shared with his wife). Don't push, in retrospect move on and find someone who is available, and wants to communicate with you. It is less stressful, and more honest.