you know what is sad? Even if the thing were to happen that you hold out hope for, even if he were to "wake up' and start being wonderful, the damage is done. My on again off again husband quit drinking 6 months ago, and none of the "old" feelings came back. I know I will be happier and healthier when I get out on my own. I know he will probably go back go back to being a depressed, lonely drunk and that makes me sad for him.
Take care of you. Your daughter deserves healthy relationships as roll models.