Forget trying to fix H. Stop trying to make him see things your way. H is not a man, he is a boy with a pretty weak, malleable identity. He doesn't know what he wants because he doesn't have much of a self.
I totally agree with OT on this. And forget all that "I never really loved you" garbage - it's right out of the manual. It's what he tells himself now to justify the fact that he wants to screw around.
Get out somewhere this weekend, for sure - you want sun, how about Vegas???
As for the legal stuff - get good advice. Don't trust H on anything - even if his intentions are good, he's likely to screw up payments and the like in his fog, so get everything ironclad if you can. The sooner you get the house valued, the better, as values are dropping and you want the maximum amount of payout. DO NOT feel guilty about getting YOUR FAIR HALF of everything. Marriage is a partnership. He did more sweat equity on the house??? Well, I'm betting you did more LAUNDRY equity on the house!!!
As for the rest - let him go, Nikki. He's never going to get his act together until he actually loses you - and maybe not even then. He's NOT a grown up man, and you are a very grown-up mature woman. Stick to the high road, keep your chin up, conduct yourself with class and dignity. This is NOT about you, this is about HIS inadequacies.
I know this hurts right now, but I'm thinking a few years from now, you will be one of those DBers with a new and much much better spouse; meanwhile he will be one of those sad guys who finally figures out what he lost in you but it's too late.