Unfortunately their recovery is up to them. I was lucky as my husband wanted out although he was still in denial. After about a week it started to dawn on him. There are lots who come and go. It’s only when they hit rock bottom that they start to realise it’s down to them.
Do other family members know, or friends? I told close family and a couple of friends immediately and forced him to go talk to his parents. I think that helped him get his act together.