My sister, in addition to being the most advanced turn-by-turn GPS system I've ever seen (I was born without whatever gene most humans, pigeons, and salmon use to find their way around), is often my social coordinator. If it weren't for her, I would probably spend the majority of my time holed up in my room playing Minecraft. That is, a larger majority of my time. And not the online/multiplayer version, either. The version in which I am the sole inhabitant of my own world.
I had friends in high school. I found a smallish circle of people with whom I shared interests but not personality. I think that's the best kind of friend you can have, because you have things to talk about but your opinions differ enough to make conversation interesting. In college, that changed.
I don't make friends easily. This does not bother me. I take a long time to decide I like someone and even then the level of social interaction I consider comfortable usually comes across as standoffishness (that's a real word) or rudeness. My close friends know this. That's why they're my close friends. That's also why they're the only type of friends I have. In high school your friend options are slim. Most kids go with the people they see on a daily basis: the people in their lunch, their clubs, their classes.
Now, no one talks to his classmate. People make friends with the people that live in their dorm. They hang out with the people in their sorority, fraternity, or other miscellaneous organization. I live at home. On top of that, I'm now surrounded by engineers. It's me, multiplied by thousands (but not as good looking and nowhere near as clever and witty). We walk from class to class with our heads down and our headphones in our ears. The second someone talks to you, your guard goes up because only the really weird kids are out to make friends. The kid that sits next to me in my computer programming class introduced himself and then asked if he smelled bad. I wish I was joking.
It was different when I walked into a humanities building for my Modern American History class (which I picked after the dismaying realization that Modern English Syntax didn't fit in my schedule). I had barely made it to the elevator before some girl walked up to me and got friend all over me. It was weird. She asked me what room I was looking for and admitted that she, too, was lost. I wasn't lost, but I didn't tell her that. I made a joke about the elevator taking forever, which she found a lot funnier than I expected. And I didn't scare her off between the elevator and the lecture hall (turns out she's in my class) because she sat next to me. She doesn't look like there's anything wrong with her...
We'll see, I guess.