I am right there with kml's advice. Give her no money and no access to your credit and/or debit cards. You will need to pick up the groceries for now on.

I would sit her down and give her some options: 1) go into rehab and get cleaned up; or 2) leave and figure out things for herself.

She has to hit rock bottom and it has to be on her timeline. You cannot continue to have her in your home drinking and/or using, especially around your children.

The AA meetings and Alanon have plenty of info to help you, but you cannot continue to have her live there w/you in that condition.

Sit quietly, the answers will reveal themselves when you least expect them to.
The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.