I'd suggest that he see a psychiatrist or therapist of some kind, and start going to meetings again. People often self-medicate depression and other mental illnesses with alcohol (which makes them worse). I've done it and know many people who also have. Good luck to you and your husband. Hopefully if he gets the help and support he needs he'll feel better soon.
and just to add......I know what it's like to be so depressed you can't even get out of bed, let alone imagine going to a meeting. Maybe it would help if you offer to drive him there and reassure him that even though he doesn't want to go he'll probably feel better afterward. If he says no, fine, but sometimes an extra helping hand can do wonders.