I've been following and I'm so sorry about this horrible situation you are in.
The main problem I see, aside from his shitty behaviour, is that he just really doesn't like you. And hasn't liked you for some time. I think PP was right that it stems from insecurity and envy of you being successful, but either way, he thinks you're up yourself, too serious, look down on him, judge him etc. You can't change his mind on this - the only way to do so would be to agree with him, and devote yourself to being a cheery adoring sex poppet. He thinks you are a bad person, whom life is too easy for, and you deserve to be punished or taken down a peg or two. Finally now he has made some money and isn't dependent on you financially any more, he can show you what it felt like for him to be stuck in a marriage that he felt he couldn't leave for financial reasons. By making you feel small and humiliated, like he did (not that you made him feel that way - that's his own neurosis. But he's projecting it onto you). He's awful.
I think it's really hard, and humiliating, and sad, and painful, to accept the reality that this is how he feels. And so there's a lot of searching and wishful thinking and misdirected anger. But he is unkind to you because he thinks you deserve it. He doesn't like you.
He won't have a good life without you. He thinks he will, but OW was only with him for the money, and eventually couldn't even tolerate him to keep the cash flowing. He is damaged and damaging and will end up bitter and lonely like so many before him.