The part of this which prevents you from walking away is about you , not her.
Her behavior is killing you emotionally, but love, you are allowing it.
There is a book called Out of the Fog , I highly recommend it.
Addiction and alcoholism aside this is one very sick woman.
Her husband left, you should too.
No contact will help you to process and come to terms with the emotional abuse you have suffered here, and you have suffered greatly.
Make it clear to her via text I supposed that you are done, go no contact, if she does not abide, restraining order. Change your phone number to private if you have to and make sure all of her emails are automatically deleted if you use email.
I suffered miserably with an alcoholic , borderline, bf for several years, there is light at the end of the tunnel. Please, I urge you to begin your own journey of healing.
Keep posting, we are here, right now you are probably thinking, I can;t let her go, you can, one day, one step at a time. The commitment is to yourself.
much love to you Katie