He is what's called a "dry drunk". Unless we also tackle our psychological problems we think the same as we did when we used. If he won't go to AA then try something else -- cognitive therapy works well. I've also heard it called "trading up addictions." We don't stop being alcoholics because we don't drink anymore. "You can't turn a pickle back into a cucumber" AA's big book says "drinking is but a symptom". What happens is constant drinking affects the mind, it changes the way we think.