I think you're realizing and seeing the incompatibility between you. It's a hard crash landing, especially when you've been working so hard on altering your own reactions and when when you're working SO hard on self improvement.

When your partner is not doing the same, it's very deflating. And it seems that no matter what you say to her, she won't budge or give you even an inch.

I hate to sound all doomsday, and I wish I could be a lot more positive about your relationship, but you're struggling SO much, and she doesn't give you any real hope for change, for improvement, for validation or for a happier marriage.

You may need to start considering the possibility of leaving her. I know you have a mixed family with children involved, but at some stage you have to ask yourself: AM I HAPPY? AM I FULFILLED? AND IS THIS HEALTHY FOR ME?

Edited to add:

It was ONLY when I told my husband I am leaving him and divorcing him, that he decided to make some much needed behavioral changes -- which he did. And as you know, there is still more to come that needs improvement. I got to another breaking point and told him (a second time), that I will leave him. He has since made additional changes and improvements, but that doesn't mean I will stay with him --- I need to see permanent and lasting changes.

But perhaps this little tidbit can give you some amount of hope, and when push comes to shove, maybe you need to lay down the line? The thought of breaking up a family and a new marriage can be daunting, but like I insinuated above, is it worth all of this CONSTANT MISERY AND PAIN? I would think not. Something to think about.