Maybe if I hadn't pushed for answers, for him to seek help, if I'd left him alone we wouldn't be where we are now, if I hadn't felt that I needed to control him, his drinking, if I'd left him alone when he left, maybe we wouldn't be getting divorced, maybe he would have gotten help.
If this. If that. If I only hadn't < fill in the blank >, maybe he would have < done something different than what he did >.
That's not how it works. He was going to do whatever it is he does. It's just the nature of the beast.
And of course you miss him. You're going through your memories and thinking of the times he was available to you. Those moments were real. But the reason why you are where you are is because he's incapable of stringing enough of those moments together in order to be a committed, responsible spouse. And that has nothing to do with you.
I wish I could tell you when the pain will stop. The truth is I don't know. My guess is you'll always have a wound from this. But while you'll have a wound, you can assimilate that wound, make it a part of you, and go forward with your life. Take care of you.