I'm sorry that you find yourself in this position.
For a drinker to stop drinking, they have to acknowledge that they have a problem, and they have to want to stop. There is lots of alcoholism on both sides of my family, and widely different outcomes. A paternal uncle drank himself to death at 59 years old. Every year, he stopped drinking for lent, just to prove to the world that he wasn't an alcoholic and could stop if he wanted to. Then on Easter Monday he would go back to the pub and that was him for another year. I believe that he had a death wish for some deep-seated psychological reason. But he knew that ѕυιcιdє is a mortal sin, so he wrongly thought that killing himself slowly over a period of years would absolve him of responsibility. At the end, he endured a lingering, painful death that was brutal to watch.
On the other side, my mother's brother is also an alcoholic. He was hospitalised just before his 40th birthday and told that if he didn't quit immediately he wouldn't see his 41st birthday. He went home, thought it through and decided to quit. That was 30 years ago and he hasn't had a drink since. Even the tragic death of his 13-year old daughter didn't push him back to drink. When he meets people for the first time, if there is socialising of any kind involved he always openly states that he is an alcoholic and therefore he can't drink alcohol.
The difference between my 2 uncles is that one wanted to live, and one didn't. So a simple, but blunt, question for your wife's friend would be just to ask him if he wants to live or die.