If he's an alcoholic, one conversation won't do anything. If he isn't ready to quit, nothing you say can make him.

What you can do is reflect to him, his behavior. Tell him that his drinking is getting in the way of your friendship. Don't talk to him about his wife etc. Keep it about you and him.

If you are willing to lose his friendship for his own good, ask him to go to an AA meeting with you. He doesn't have to talk or anything. He can pretend that you are the alcoholic and he's just coming along as your friend. Hopefully, he hears something that stikes a chord.

Recommend to his wife, that she should go to Al-Anon. Often the alcoholic only gets better, when the people in his life learn how not to enable him.

Best of luck.