I'm certainly no expert, and am still finding my own way, but I can reiterate what cli says. Above all, protect yourself as much as possible.
One thing seems apparent; Rock Bottom is a different place for everyone, and some don't seem to reach it until it's too late. I thought my AW would hit rock bottom when she got drunk and broke her ankle two years ago, requiring $30,000 worth of surgery. She stopped for a few months, but took up drinking again.
We ran up thousands in Credit Card debt, and I took responsibility for my part, thinking it was "our problem". I quit spending, but now she's maxed out another card all by herself, without my knowledge.
And still she drinks, even after tearful confessions and begging forgiveness. No DUI yet, but I think it's just a matter of time.
Take care of yourself, and good luck.