Welcome to SR, but I am sorry for the circumstances that brought you here.
He is going to do what he is going to do, unfortunately. With his heavy drinking, the Zoloft will not do any good either. Alcohol is a depressant.
I too recommend the reading that Catlovermi suggested to you. "Codependent No More" by Melody Beattie is an excellent starter book.
I'd also like to suggest Alanon as there you will find face-to-face support among those who understand. Alcoholism affects everyone in its path, and we need a way to heal ourselves and live a full life in spite of what the alcoholic is/isn't doing.
Alanon has been invaluable to me, and I practice the principles of Alanon in all areas of my life.
I hope you continue to post!