How do you get a girlfriend when you don't drink or do drugs?

First of all, having a drink or two at a bar on Friday night hardly qualifies a girl as a drunk, so make sure you're labeling correctly. If you're intolerant of drinking, yes it will rule out a lot of girls. But there are plenty who don't engage in those activities. Join a club: cooking, dancing, musical instrument, etc. You're bound to meet someone eventually.