So much of what I read reminds me of ME.
I understand the hurt and the anger of being rejected. You'd think we'd be used to it by now but it still is a kick in the gut. When my AH said he did not think he wanted to be married anymore my first reaction was "I put up with your drunk a** all these years and you don't know if you want to be married to ME?" WTF????
And then when we separated he went no contact -MIA for quite a while. It was so hard for me to have had this person in my life for 30 years and then -nothing.
But Al ANon helped and I now see how it was a blessing because had I had contact I would have been less able to detach and see things clearly.
So he filed for divorce. Maybe he is waiting for you to call his bluff. Maybe its his way of manipulating you. Maybe, maybe, maybe...
Bottom line is that he wont stop drinking-you can't make him. So unless you want to continue being married to an alcoholic, this is a get out of jail free card.
It sucks, it hurts like hell. But it gets better and as my therapist reminds me-few decisions we make in life are not reversible. If and when his circumstances change, you can decide if you want to have any kind of relationship with him.
Keep coming back. I'd be interested to hear if he follows through with this.