Yay I'm so glad you were able to share with your mother and get her support! It will be so helpful to you.
I remember when I finally admitted to my parents (but they already knew) that my H was not only an alcoholic but a drug user, and an abuser. It was like a giant weight being lifted off my shoulders. I'd kept secrets from them for years, thinking I was protecting them from my poor choices, when in fact I was creating a divide between us that AH willingly exploited to isolate and control me further.
I wonder...is there any way for you to move out before August? Would your mother be able to help you brainstorm some ideas? August seems like a long ways off when you're living with a sabbotaging alcoholic spouse...