My drinking habits are pretty erratic. Before I started living on my own I drank perhaps five to ten times a year, y'know, at parties and stuff, and usually just a beer or two (but I got drunk really fast).
Then I went to university and the introduction week was practically made out of beer. I even had to miss an entire day after a cantus the night before (for the unenlightened: beer, song, and more beer). Since then, I've gained some weight and I can stand alcohol a little better (i.e. I can actually stand).
After I moved out it dawned on me that I could basically do whatever I liked, including drinking. I'm not that good at making friends, so a lot of evenings I was just sitting in my room getting drunk. I sobered up after I failed maths pretty badly (lectures of which took place early in the morning and I almost always had a headache).
I made some more friends after that so now I'm back to only drinking at parties. It's picking up a little because I have this amazingly sweet girlfriend to go out with as of recently, but she won't let me get drunk (which I really appreciate).
So now it's at once every other week/once a month I guess.