Great thought piece, appreciate your vulnerability. I think what you are calling attention to is difficulty so many people have differentiating codependency (and enabling) vs doing things for the kids.

Its possible your set up could have worked, but if it had, you might still be with the guy, right? He would be a different person. Since he has terrible boundaries and no respect for you and your experience, I congratulate you on your ability to come to terms with this and realize he is an adult and you deserve to have your own space and that in the long run, healthy boundaries and accountability is better for everyone, kids included.