I am so sorry for what you are going through. I do think there is a time in a marriage that there is no going back, and maybe that is where he is. For the sake of your children, I hope he remains sober and in a good place. You are in a stagnant place, so I would think it would be very hard to move forward when you have not divorced. If he also has not filed, would it not be wise to sit down with him and have a very real conversation about the future?
I understand it's painful, but if there is no future it may be wise to go through the pain of divorcing so you can at least actually move forward.
Big huge hugs.