Erin, my second husband is somehow still alive, but I have no idea how. I would have expected him to come to a similar end a good ten or more years ago. He's still drinking.
I came to peace with it when I left--I don't know what I'd feel, at this point, if I learned that he died. I suppose I did most of my grieving when we split up.
It IS a waste. He had many good qualities, but they were all buried under the alcohol. I don't think it's a matter of "choosing" to check out that way. When you're in it, you can't see another, viable way to live. I was fortunate that I was able to escape, but there was a time when I thought I was doomed to the same fate. I don't consider myself any braver, or smarter than many who never make it out. I don't know why it goes one way for some and another way for others. In a way, it's like many other diseases, where some people make it and others don't. And it isn't always a matter of free will or choice.
Let yourself feel what you feel, right now. It's a loss, and a waste. He's free from suffering now, and your own pain will ease with time.