Any way to pick him up?

My boyfriend is at a real low right now. He has had them before but ones this bad are quite rare and its not been like this since before xmas.

It's depression and he's barely talking to me. He's at work right now. Sometimes he doesn't mind his job and has a good night but today he was already down and its not helping. He gets down about his job and that he has no friends, although he does and he actually has plenty of plans with people coming up he wants to cancel.

I just don't know what to do. So far I have tried to keep my distance, sort of only talking to him when he talks to me first, otherwise I annoy him being needy and wanting intimacy. I always say the wrong things trying to be positive and as soon as I say something along the lines of it'll get better then he shuts down and stops talking.

I just worry about him and it hurts me to see him like it. I get why he feels bored as I do too but I can find enjoyment in little things to get me through whereas he hates everything. I even bought him his favourite treats and he doesn't care for them.

Does anyone have any ideas at all of something I can do for him? Or how to pull him out of this dark time?

(He won't see a doctor or anything like that and I can't persuade him to. He usually smokes weed but he ran out so hasn't for a week or so. Instead he's been drinking spirits and mixers each night while he plays xbox. But getting help isn't really an option since he won't talk or consider it yet)