I have gone back and read your whole sitch. I completely understand your situation, I have a lot of similarities in my sitch.
I may have some insight into why your husband is acting the way he is. You mentioned a few pages back that he MAY be depressed. HE IS! I have been there and done some of the things he did. He started messing with OW after the business was hurting. Reason being is that he felt like less of a man. Felt unworthy of you and slept with the OW becasue he felt she was like you but would not judge you. I did all of this EXCEPT cheat. I tried to leave her at the time when my business failed and tried to make it seem like it was all her fault so that she would accept it. But the reason I was doing it was becasue at the time I felt she deserved better. I forgot my vows. Instead of sharing my problems with my wife, I tried to conquer the world and solve all of our problems myself. Problem is she resented me for shutting her out. Just like you felt. When he shut you out you called to find out what was going on. He saw it as clinging even though you were trying to help. I did the same thing. He felt like less of a man becasue he could not solve the problem on his own. Also you mentioned him getting into other field when his other business was booming. Trust me he remembers that too. So now he wished he listened to you and is mad at himself. He is beating himself up as much as you are. He just shows it by blaming everybody but himself. I did that too until the day my W left me!!! I have turned my life totally around now and working to solve the problems between us. I am struggling to understand what she is thinking. But I hope this lets you understand a little of what is probably going on in his head. If you have any questions, please ask, maybe I can answer some others.
Hang in there. Maybe read Men are from Mars Women are from Venus, that really helped me understand how to interact better with W. I wish I had read it years ago. ((HUGS))
