His higher power has spoken through his body with liver failure.
It is his choice to listen to it or not.
What a horrible decision to have to make. Your serenity, or him. Seems you can't have both.
I can't tell you what to do. I know though that if I was in your situation, if he came back to the house with me and relapsed, I would have to kick him out, whatever it took.
At that point I would see myself as enabling him, and playing a part in his death wish.