Should I rid this person from my life?

I'm in a similar situation with my mom, minus the drugs and alcohol. However, I've simply distanced myself from her and when the time comes, she will realize what she has lost. Its not your loss, its hers. I love my mother, too, but enough is enough when it comes right down to it. Its up to you to make the decision. Maybe simply contact her through phone and just don't visit for some time. If a fight happens on the phone, you can always just hang up. You don't have to put up with it.