First, I am amazed at how many non-drinking, non-smoking people there are. I live in surroundings where all these things are considered normal and even desirable. Okay, maybe not the drugs and the casual sex (especially if you're a woman), but drinking and smoking is taken in such way that people think it's "cute" when your four year old son/daughter tries beer. So, for many years, I believed myself to be some sort of a freak because everybody looked at me like a retard for not liking alcohol. It took me hours of explaining that I just don't like those things, much similar to them not liking skiing or watching movies.
Second, no, I do not indulge in any of those things and I am happy with my life because there are other things that I can enjoy with. I know this has been said a lot on the last pages, but I'd like to share my opinion as well. Happiness is not something that depends on the way you seek it; some people seek it with alcohol or smoking, some seek it with gardening or playing games. I seek it with reading, writing, playing games, watching movies, exploring, enjoying my college, my friends. My main reason for not indulging in drinking is the fact that I am (probably) alcohol intolerant (as I am known for having strange reactions even to the sole smell of alcohol; it makes me sick even when some of my family members put alcoholic beverage on the table). The reason for not smoking is similar; I tend to get headaches even from being exposed to cigarette smoke for a few minutes (yes, going to bars is really hard for me). Drugs are not something that interest me in any way (besides, I get a lot "Are you on drugs?" questions which may mean that I can be as funny/interesting when sober just as someone that takes drugs; I guess that's a plus for me because I'm naturally silly when I want to be). Casual sex does not interest me either, nor did I ever seek a strictly sexual relationship. Drinking, smoking, taking drugs and having casual sex sounds really boring to me (and painful when it comes to first two). If somebody offers me a night at the club, drinking, smoking (provided I can do those things), taking drugs and having casual sex as opposed to staying home with a good movie, a book and having fun chatting with my friends, I'll choose the latter instantly and never ever regret it. Strange world, isn't it?
Third, I respect any way(s) of seeking happiness, but there is a slight probability that we will not get along if you drink, smoke, take drugs and see me as a sexual object.
Fourth (and last, I swear), I am not always happy. But no one is. We all have our moments of sadness or not being happy about things in general. I don't think that my activities have anything to do with the fact that we are all still just human beings that tend to experience different emotions in their lifetime. As a matter of fact, I think my activities helped me a lot when I wasn't feeling well; just as someone feels better after smoking or drinking, I feel better after I watch a movie, read a book, or write a story.
I hope these eight pages of responses gave you the idea of what differences in people really are and that you can now grasp our way of perceiving happiness, at least a little bit.