Hello there Pandora
I'm so sorry to hear that your family is getting ripped apart by your Mom's alcoholism. Like GiveLove said, you need to learn more about this disease and how it works. You can start by reading thru the "sticky posts" at the top of this forum. Then grab your phone book, call up the local office of Al-Anon and go check out a few of their meetings. They have _great_ book and pamphlets that I have found incredibly helpful.
We've all been thru something similar to what you are describing. That details are different, but we all have a loved one that is tangled up in addiction. You, and your family, don't have to fight this alone anymore.
Mike