I would say that if you don't want a divorce, don't do anything (but consult with a lawyer to make sure that you don't get stuck in some mess). Make him do all the paperwork.
GAL is good advice, but I think that I would also say that it takes a while to get detached and get to the point where you are not hurting enormously.
I found that going dark early in the crisis was good; it helped me detach and not be angry. You have to get rid of anger before you can become friends and then possibly romantic--if it is going to happen.
Your H's crisis seems to have come on abruptly. My H's came on slowly and is probably going to exit slowly. I think the quick crises are the ones that burn out quickly, too.
M: 16 years Bomb 4/07 OW 20s long gone Divorced 11/09 I remarried New Guy Cooperative r w/X regarding D
