At some level, marriage involves multiple legal contracts. To dissolve a marriage, you have to take legal action to change those contracts.
For example, if your AH has a pension, you are entitled to some future benefit from it, and that has to be obtained through legal documents. You have joint property, and a joint mortgage that you need to be definitively and legally extracted from.
I found that my now XAH used the divorce process as a carrot and a bludgeon to try to keep me involved with him and to try to scare me that I could not survive financially on my own and NEEDED to go back to him.
You may remember that he sent me spreadsheet after spreadsheet, so many that I threatened to paper his bathroom with them, of supposed divorce settlement proposals that essentially gave him everything, and me nothing.
This is such fertile ground for quacking that, from my experience, I'd say, just don't go there at all, ever. Get a tough lawyer and let them do their job. Don't leave anything in joint possession, even if it means moving and selling the house right now. Any detail that dangles out there is an opportunity for an alcoholic, with their mixed up emotions and divided motivation, to use as a hook to keep you entangled.
You need to be free, and that will cost whatever it will cost.
Best wishes,
ShootingStar1