I'd call my x husband "functional" in that, he drinks daily and still manages to go to work, bring home a paycheck, and hasn't had any DUIs or alcohol-induced run ins with the law. He does however have chronic intestinal problems, he eats poorly when he does eat (beer is filling!), he complains regularly of many mysterious aches and pains, his hands have *always* trembled ever since I met him, he's gained a good deal of weight since we met (probably 20+ pounds) and his teeth are rotting in his mouth. His personal hygiene has always been somewhat lacking, but whenever he's on a bender, he's even more disgusting.
Right now, because he's trying to look like Super Dad to avoid getting dragged into a custody battle with me, he's doing alright. I forsee that at some point, some kind of DRAMA in his life will push him to drink more heavily and then things will begin spiraling out of hand. I suspect that at some point, there will be a girl, then a pregnancy (heck, it's happened before...I'm #4 on the list!), and then the excuse to start drinking the strong stuff will present itself. Or he'll lose his job. Or his son will return to his mother's. Or the French people will take over the world. Or something.
It's like a sad sick waiting game. I wish he'd find his way to recovery, but I know it's not going to happen.