Mama...
You're doing so well in enforcing those boundaries and putting your needs and your kids needs first. I know its not easy but your making a new, peaceful life for yourself one step at a time. The steps get easier as you go.
I know the hate your AH spews must hurt. My exh's words always seemed to send me reeling in the beginning. This is, after all, the man you fell in love with (or at least he LOOKS like the person you fell in love with) and sometimes its hard to remember how much you have both changed as a result of his addiction. Deep down I believe he knows why you are doing this and he respects you for it even though he's going to quack and say the opposite in order to maintain his lifestyle. My exah would tell me how much he hated me...how selfish I was...how I wasn't supportive enough. He would throw our marriage vows in my face and make me feel guilty and doubt myself. But I stuck to my guns and after my exah got some clean time under his belt, he told me that he would have continued doing what he was doing as long as I allowed him to do it. He admits that as much as he hated me at the time, he knew I did the right thing even as he spewed his venom at me. Even though I didn't need this validation from him at the time he offered it, I have to admit that it meant alot to me to hear him admit it.
My point, I guess, is that you aren't just doing this for yourself . If taking this step helps your ah hit his 'bottom' sooner, than your actually doing him a favor in the long run. He's where he is as a result of HIS actions. Not yours.
The very life your saving could be his. Just remember that when he quacks at you, screams and yells and does whatever he might do to try and get you to bend on your new boundaries. And if this isn't his 'bottom', your so much better off not being there to witness it personally when it does come.
You're a great mom. You're a strong woman. Your kids are so blessed to have one rational, reasonable parent in their corner.
Hugs and admiration to you.