It's so hard coming to this realization, I know.
I would encourage you to find an al-anon meeting in your area and start going. It's not for everyone, but I know it's definitely helped me learn to detach with love from my alcoholic/codependent family.
Your first priority here needs to be you, your sanity and your children. Don't lose sight of that. Keep reading and posting here, as well. This place has also been very helpful for me. Hugs and love to you.