Throwing out alcohol is useless. I would stop that now. I would not try to do anything to stop her from drinking because - that's another brick wall if they want to they will.
You need to protect yourself legally. She is driving drunk - what kind of liability are you subject to? Is your name on the car? Is it your insurance?
Back in the day I worked in Bankruptcy and Foreclosure - many a case where a spouse was in BR due to the alcoholism or addiction of their wife/husband. please don't let that happen to you.