I only wanted to get married once, so when I felt I was ready to handle it, I looked at my relationships and noticed that boyfriends get tired of girlfriends, and vice versa, but you never get tired of your friends.
Men even contract the dirty, filthy habit of chewing tobacco, and when the habit gets a good hold upon them they are never satisfied except when they have a wad of the stuff in their mouth. So with drinking. It is largely a habit.