Welcome to SR - I am sorry that you find yourself here. Please read and share as you feel you can - you will find much wisdom here.
I am new here myself and have recently made the decision to leave. My A is not ready to quit drinking and my son and I have been through enough. To be honest even if he came to me and said ok I am ready to quit - I still would be leaving, I love him very much but I love my son and myself more.
You asked when do you know when enough is enough.... you will just know.
Again welcome,
shakarris