First of all, this is validation that strong DB techniques can flip the script.
Secondly, it reinforces that once you detach enough to wake them up, you’ll often find yourself in a position where you don’t know if you want them back.
He’s probably going to pile on the pressure for a quick resolution because now he’s vulnerable. He’s ended it with her, burned the bridge, but he doesn’t know if you’re going to take him back. He will be feeling very anxious and vulnerable, so he’ll try and accelerate this as much as he can.
It’s important that you do this very slowly. What you’ve told him - not moving back in, getting IC and alcoholism help, making sure he’s actually going to change - they’re all really good, sensible and measured responses from you. Well done.
Remember, you have the upper hand atm. Just because he’s struggling, doesn’t mean you should rush anything or be there to catch and save him. Let him sweat it. Let him feel the seriousness of his actions. The longer you make him wait, the more likely he is to actually do the work and learn the value of a trusting, monogamous relationship.
DNJ’s advice was spot on. You do you, you protect you, you love you - if he is really worth your time/effort/love/trust, he’ll prove it through actions no over time. So far (except for dumping OW) it’s mainly just words.