Elsie,
The question isn't "will he ever quit"? the question is do you want to be with this man, right now, the way he is today, right now, not next month, year or decade.
I don't think we have the crystal balls that determine if and when someone will find sobriety, but we have the power to decide what we want in our lives at this moment.
And oh, from what you have said, I can't imagine that he is even remotely interested in quitting. Or does he always act completely opposite from what he's thinking and doing?