The first thing I have to say is how much I regret you have
had to wait so long for an answer to your post. Please rest assured it
is nothing to do with you, or the subject of your post. This system we
use here to see and answer posts unfortunately does not always behave as
we would like. We wish it did.
OK, so a belated welcome to the the Forum, writing that first post is
something I'd imagine you found hard to do. It does help as there are
all sorts of people here, all volunteers, who try to share their
experience to smooth the path of others.
It can very hard in your position to understand what is happening and know what to do. There is no real guide or roadmap, and all sorts of thoughts can creep in, particularly wondering if you have done enough or missed something, feeling frustrated, even that the relationship might be over.
I can't answer all your questions, I can say letting the person you love know you will be there -a constant they can look to when needed - is most iportant. Also that they get competent medical help, which now has started.
Incidentally being placed on medication is not straightforward, quite apart from the fact different people react in differing ways, there is a lead-in time when temporary effects may appear and in your husband's case there is the use of alcohol which may negate med's useful effects, and in fact make matters worse.
I'd strongly suggest he tells his doctor of the alcohol use.
Wanting to be apart is hard to understand, particularly if you had a close relationship and were a team.
I can say when depression hit me hard it took up all my mind, it narrowed down my thoughts to a few seemingly insoluble problems and left no room in my mind or energy to think of other things - or people. The desire for being alone was very strong, and efforts by others to make contact and try to understand were regrettably met with resentment or impatience.
In time as treatment took hold - in my case- this passed.
As you have said you have both had hard things to deal with this year. You are in a stressful and worried position and have had to face those same things too without partner support.
May I ask what supports you have to get you through? A GP to talk with? Maybe a family member who cares and you can talk with. It makes a huge difference. My wife had her mum, and she could kept going partly because of that
I hope you come back -despite the delay -and we get to talk some more