Welcome!
I can't tell you what to do, but I can tell you what I know to be true of alcoholics.
Alcoholism is progressive. It Does get worse if untreated.
What you saw on the date is a good indicator of future behavior. In the early phase of dating, most folks have the honeymoon period. When we are trying to put our best face forward. Your guy has shown you up front what he is all about: substance abuse. Believe him.
I had to let go of my fantasies of potential in others. What you see is what you get.
I had fantasies of helping my Alcoholic ex-Husband become all he could potentially be. Honey, even the marines couldn't help him be more than a manipulating, lying, denying, charming, handsome, funny, minimizing, blame-shifting alcoholic!
I learned at this site about the 3 C's of addiction:
I did not Cause it
I can not Control it
I will not Cure it.
The addiction, it's consequences, and any future recovery belong to the adult with the issue.