Part of what I had to learn is that I did not have to keep talking until I said something my xah would accept as 'good enough'. I could say 'tonight doesn't work for me.' or 'I'm tired tonight and want to be alone.' I don't have to keep going and offering up reasons he feels worthy. I don't even have to say why. It might just be a feeling and I don't know why, I might not feel like telling, I might know it will just be another circular discussion going nowhere. You don't have to tell him why. He is not sober he isn't going to 'hear' it anyway.
I even began to say "I don't know." to things when I really didn't know. Imagine that! His head about popped off. He kept badgering and I just stuck with it. Sometimes people really don't know. "I can't decide that now." was also one he hated. I had always felt like I needed to come up with *the* answer and then stick to it right now, no matter what. He had gotten used to that and then when I changed my mind, he'd go on and on and on about it. I didn't owe him, or myself, an answer right then and there. I could think it through. If I made a mistake I could say "I made a mistake and I'm changing my mind."
Those were big things for me.
I want to add my xah is not violent and had shown no physical aggression to me what so ever. Have you spoke with a domestic violence person? I think their advice should be followed first, whatever that might me.