At University, I went to quite a few parties, mostly those that were dorm parties where you didn't need an invitation. Do you have those over there? (Basically they were at the dorm so you just went with your roommate/s. Especially if you couldn't sleep because of the noise anyway. And you could go back any time if you wanted.)
Or any parties with international students? (My cousin says here in Slovenia, Europe, they can be awesome too.)
I didn't drink and do drugs either, some of my friends didn't either. Some just had a little to drink.
Some thought it was weird, but I could dance all night with just water. Tap water, to be precise.
(Maybe I had a beer or a glass of wine at times, nothing much, and found I preferred dancing without. In fact, later on, when I did have some alcohol, though still not much, I found I COULDN'T dance so much! Ha!)
/Just a beer can be different than a Breezer or something like that too, Breezers are worse, lol./
Sooo... If you go to a party, it doesn't mean you have to take anything.. It depends what kind of party it is, what kind of people.. what kind of music.. (I liked it best if I knew some people there..) Yes, some parties are drinking parties and you may not get invited, or feel sucky there and leave. Not sure if anyone can survive techno/house sober. Otherwise, with good music, I don't need anything else... (Plus, beer can make you do stupid things, lol.) Yes, some people thought I was stoned at times - nope, that's just my personality - I can just have fun without anything iffy!
And yeah, there were dorms where like whole floors of people flunked the year cause they were playing cards and partying so much. It's better to not be in that kind of dorm.
What am I saying? You're totally not a loser by not going to the parties. The opposite. You are admirable and possibly a high achiever. And most parties are the same and some can be kinda boring, depends on music & people. I didn't like too big events either. Some people never go to parties and are totally okay with that.
If you do go, there are ways to not compromise your integrity and still have fun.