As for the discovery, well....the night he made his feelings known was pre-bomb and she came home and told me. Of course she told me under the assumption of no way would it happen. Then when she dropped the bomb and we went to MC she confessed that she wanted to see him and that was the route she was going to take.
I just find that a little odd. That, and the thing you said about her strong reaction to even the THOUGHT of you moving on without her, makes me feel that she is crying out for you to FIGHT for her.
Just my gut, but most spouses who are "done" don't make grand pronouncements about their infidelity without getting dragged kicking and screaming into them. And they usually try to talk their betrayed spouse INTO dating, not the other way around.