Sounds like his pickling on the inside is keeping him going!! There is no rhyme or reason. We all know someone who has smoked to a ripe old age and the ravages of smoking haven't caught up with them!
It's about you, it's about what you're comfortable with. As most have said once you start treatment you may not have the want for an alcoholic beverage and then when you do you may decide that doesn't taste how I remember it to be. Problem with wine in particular is lack of labelling so do you really know what you are drinking apart from the % proof?