Deb - I just wanted to give you a (hug). And you never know - if H never thought he'd have an A and he did have one, then perhaps he'll see a counselor sometime if he feels he needs to (probably not unless he is worried about really losing you).
It sounds like he is still trying to compare the two of you - and trying to talk himself (mostly) out of her. But there has to be SOMETHING that drew her to him, and something that has made him not stop thinking about her.
Have you thought about taking up walking yourself? Or bike riding? I am not sure if you had joined a gym or not - but definitely do something you enjoy that will help you get healthy (not just thin, but healthy). Do it for yourself. A healthy Deb is a much happier Deb, no matter what the outcome of your marital situation.
My thoughts are a bit disjointed today - I've been sick for a few days. But don't let him get to you with criticism's and such. You aren't the one who has won anything yet - he is. He has a wife who keeps being there for him even after all he's done. You have a guy who has lied, cheated, and spent your money on another woman. Who is the winner here?
Oh - don't tell him a reason why you go out. Just say that you went shopping. You aren't a prisoner of your home. Leave him a note, nothing elaborate "I went to the gym". I went shopping, be back in a couple of hours". No need to go into details and such.
