Hi Hsperanza, I think it's harder when they stop drinking and we get our hopes up, then they start again.
I'm going to assume you live with her. Are you in a position to move out? It sounds like you would benefit from a break.
You don't have to look after your mother. Its not your duty because she is an adult and you have your own life to live. Maybe your would benefit from going to Al-anon, which is for the families of As. You will meet many people who have been in your shoes in one way or another.