I hear what you are saying. It so clear. Mine is the same, except she never got the DWI, and doesn't/hasn't worked.
Yours has not hit rock bottom. You are still there, picking up the pieces. If you've read my posts, you know I'm gonna say.........RUN. She put her selfish needs above all else. And now must face the consequence.
I'm familiar with the rage at spilling the beans. they don't like to face the reality of what they are and do. In their mind, we are the problem. they don't have any problems. Can you see the disconnect from reality? In order to keep her problem a secret, she was perfectly ok with leaving your child at home alone. What reasonable parent would do this? You know the answer.
She will not change. There is no catalyst for change. Why should she?
The DWI is a plus for your side in a custody battle. Go lawyer up, take the next step, move on. And find someone who can behave like an adult. I wish I would have left mine 20 years ago. But here I am. Still trying to make it work. My life is a little better than it was. but it is a far cry from what I "thought" it would be.
She crossed the line, you have no obligation to stay. But ultimately, the decision is yours and yours alone. I know what I'd do, and what I wish I had done.