Just a reminder.
Alcoholics lie. Even when the truth works just fine, they lie. They are selfish. They say and do anything to get what they want. They have an ulterior motive for most everything they do. They blame us for their problems, and the project their problems on to us. There is nothing "civil" about ending a marriage to an alcoholic. It will be ugly, then peaceful.
What does he have to lose by leaving early, demanding to come back to the home, and exactly who cares what his mom says? If she is concerned, how about telling him to move in with his mom? Send him home to mommy where maybe she can help him grow into a man.
What to do? there are several paths. In Texas, you can not kick him out of his house. He has a right to be there. But, you can file a restraining order banning him from the home. It will take a couple days, and he has to be served with the papers from a 3rd party. Any family lawyer can do this lickity split for you. He can counter file, but the judges are pretty fed up with alcoholics. If you have evidence of the detox, and alcohol problems, he'll be out for the duration. And you can file the divorce papers yourself at the same time if you want to. Costs about 300 bucks.
You can try to peacefully co-exist in your home. But you know it will not be "even". It will be on his terms. You will have to accept that.
Or you can just pack your stuff and move. Take him out of the equation, and spend money from your joint account on your place. Pre pay for 3 months of rent at an apartment. You have just as much right to the money and a place to live as he does.
There are always answers to these stumbling blocks. It is best to do what you want, and leave them quacking to themselves.