I'm not sure either. My defination would be one drink when sober, would start the downward spiral, and dependency again.
Lots of people drink too much at times to escape reality, i don't think that necessarily makes them an alcoholic though.
I just think it would be great if fasting made alcoholics, like normal again in that respect. Although i'm not sure if the alcoholic gene exists, and that person if drinking would over time still develop a problem even on small quantities.