Well, you go no contact by blocking that email.
Sotired, it's really important to remember and accept that for all his behavior, he is NOT a little kid. He is not helpless. He can and must learn to fend for himself, but he won't as long as you are there to prop him up.
I understand it feels cruel to divorce him, but objectively, it is not. All that piece of paper is doing is keeping both of you from moving on. It's not your job to make sure he moves on in the right way. You deserve the same kind of attention and respect you think he deserves.