See if you can't get your hands on a couple of books, "Codependent No More" by Melody Beattie, and "Women Who Love Too Much" by Robin Norwood.
I would also encourage you to look for Alanon meetings in your area for face-to-face support with this.
A counselor who specializes in addictions/alcoholism could also be a huge help in you sorting out why you are so enmeshed with this fellow.