My husband was a functional alcoholic for the first few years we were married. He started calling in sick to work after his weekly dart games. He could drink *a lot* before achieving a hangover: that's because his tolerance was so high from drinking so much, for so long.
In 25 years he went from computer programmer to retail sales clerk to maintenance man at a private school. Fired from three jobs in six years.
You think your love will fix him. It just won't. If not for you, for your daughter, reconsider this. You aren't even boyfriend and girlfriend. Is this what you want to teach your daughter? That this kind of relationship, this kind of limited partner, is what she should expect?
Is this the standard you want to set for her?