SD has learned there is nothing she can do or say that will affect her mother's drinking so she smartly pulled away. Saying she wants her mother to not be an alcoholic is said in jest because she knows that isn't going to happen. Mom, the self-centered, self-involved alcoholic that she is has no interest in what her daughter wants. It's about me, me, me. And, active alcoholics want codependents around because it helps them drink, gives some self-esteem, whatever. But daughter is healthy and wants nothing to do with it.
Why are you getting involved? It's between SD and her mother. Did either of them ask for your advice and help?