Anecdotally, I've noticed that people who don't drink at all tend to be more social in general, while people who often drink in social settings can find it hard

Anecdotally, I've noticed that people who don't drink at all tend to be more social in general, while people who often drink in social settings can find it hard to be social if they're not drunk (and often if both parties aren't drunk). Hence all the replies here that equate alcohol with being social and absence of alcohol with social isolation. Alcohol has become a crutch. Are you using "drunk" as a term for not being sober, or "drunk" in the common usage where someone is noticeably impaired by the quantity of alcohol they have drank? Because it's quite possible to drink alcohol without actually getting the point of stumbling or slurring your words noticeably.