Not official medical advice, but i suggest switching out alcohol for marijuana - less depressant effects and safer overall. If you guys are into drugs/psychedelics, would he worthwhile going for a mushroom “trip” while he feels emotionally more stable - I’ve seen/heard anecdotes of this working.
I went through something similar last year after a close family death. I found a series of these podcasts very grounding and helpful too.
https://youtu.be/LTGGyQS1fZE?si=KDb7Qh-wFS08QJeJ