I think all you can really do is live by example.
We know all-too-well the demons of alcoholism. "Tough love" never worked on me. Family members or friends policing my intake definitely never worked. None of it really did. And if he has an enabler in his life, that's another layer of complicated.
What he probably needs is some serious outpatient support at a recovery center, the guidance of a doctor, and a realistic view of what his life can be now. He probably feels helpless and has surrendered, and alcohol serves to silence what I imagine is a lot of fear, regret, shame, etc...
I wish I had better advice. If you've said your piece, you could try talking to his wife separately and stage an intervention of some kind, but I don't know much about that or how successful they are (and if there's means to send him somewhere that could help). Good luck man, I've been there.