NoelleR, those are valid points and questions, and I'll think about them. But I think I ought to give a little more context to my statement of the main problem is that he's absent from our relationship. I had been trying for years to talk to him about how distant he was, and that his choice to fall asleep on the couch in front of the TV and get up and go downstairs to read and drink when I went to bed was having a very negative affect on our relationship. I told him that I needed him to go to bed at the same time as me, at least some nights of the week, and all these conversations went nowhere and resulted in absolutely no change on his part. My two conclusions from years of trying to have better communication with him and letting him know what my needs are, either his need for alcohol is playing a big part in his decision to nap while I'm awake and drink and read in solitude late into the night, or he doesn't give a crap about our relationship or my needs. Either conclusion isn't very good at this point, but yes, there are weird ways in which he doesn't fit all the alcoholic characteristics to a "T", but it seems safe to me to say that anyone who drinks every day, even when they're sick, has some dependence on alcohol. And even if it isn't causing a lot of outward problems in his life, I do believe it has been a part of causing a wedge between us.
So perhaps I'll try to find some time to talk to him about some things this weekend, it's really hard to find time to talk to him when our evenings consist of watching the news, fixing and eating dinner, cleaning up, then he falls asleep on the couch till I go to bed. I do really appreciate everyone's encouragement and perspectives!