You're not pathetic and it's not your fault. You don't deserve to be treated like this.
You've stayed because twenty years is a lot to walk away from. Because you wanted to see the best in someone you've loved. Because you had real fears about your ability to reconstruct your life without him. That's not foolish. Don't beat yourself up for those choices.
I don't think you're stupid, OP. The opposite, actually. Look back over your posts. Your gut instinct is spot on. That's what I think. You can read this guy like a book. He's done an absolute number on you, trying to break you down, but you're still in there seeing straight through him. You should be proud of that.
He has tried to keep you at home (in "his" precious house) because it gives him more control over you. The entire reason he encouraged this was so that he could create a justification to talk to you the way he does. Because he needs an outlet for his emotions, and taking aim at you is the one he's settled on. But you know something else, OP? For all he acts like Mr Intelligent and Mr Reasonable, and tries to convince you he could turn it all around on you if you went for help, that's not true.
He's terrified of you. That's the truth, OP. Shining through clear as day in your posts. The sort of man he's pretending to be doesn't talk to his wife in such a vile way. And he certainly doesn't lay hands on her. That's why he's so angry you screamed. That's why he has systematically cut you off from your support group. That's why he tries to shame you out of going to the refuge. He's desperate to protect his own self image. He knows it'll all come crumbling down if you tell the truth about him.
You're right, he won't change. I know you're scared to be alone, OP. But there is support out there to help you. And maybe you won't have the house or the puppies anymore, if you leave. But you know what else you won't have in your life? Him. Don't underestimate what a weight will be lifted from you when you don't have to deal with him every day. No more of those awful, gut-wrenching comments that make you feel two feet tall. No more of him sabotaging everything you try to do for yourself. No more violence, and listening to him tell you afterwards that you deserved the violence. It'll all be gone. And I have a funny feeling that once you're out of that house, and away from his oppressive presence, you'll start to see him even more clearly than you do now.
Please reach out to the support groups that have been given in the thread. You can do this. You're much stronger than you think you are. We can all see it, even if you can't right now 🌺
He's a sad, unfixable little man, and he's had twenty years of chances. Listen to your gut. It's time to go.