it's a strange phenomenon indeed. It was easier before college because everyone was kind of stuck with each other. in college, everyone has their own agenda.
I wouldn't say i'm anti-social, but i haven't been able to really make any close friends. I could chat just fine in class or at the library with friends. I haven't really gotten to the point where i just want to hang out with this person outside of school just cause i'm close friends. i don't know how to explain it.
Basically, i don't have any friends that i can just hang outside of school with. I have one that i kept from high school, some others from high school i stopped hanging around because we just didn't click.
Basically you just have to put yourself out there. Because if you don't, the other person might not. Everyone in college is starting at a new stage. Everyone's new, and have to start over making new friends. And they might just be like you, wanting someone to all of a sudden step up and make friends. [i'm saying "you" in the general sense.]
One thing i noticed is that your socializing skills can deteriorate!!!!! Without the interaction, you begin to really lose confidence when surrounded by people. You aren't as likely to be the first voice. So once in a while, you might want to practice your speech. I think it'll help with thinking on your feet so you don't get caught up in awkward situations.
You know what i mean. People like to joke with each other, and sometimes you might not know how to react.
then again, there are just those people who like to just say stuff. they get on my nerves. This one girl i knew, she's nice and all, but she liked to just spew lies every once in a while. It gets old... really quickly. Also be careful of those girls who kind of use you. I helped this one girl in my class, and I used to kind of be this mediator between this other girl and her, but when they became friends, they kind of totally just left me in the dust. i was a little shocked because although they didn't try to ignore me or anything, i could definitely feel this sort or wall around them, and i was on the other side of it!
To everyone who feels lonely: I feel your pain. right now i feel pretty depressed. I'm far away from my high school friends. in fact, i haven't seen them for 3 years. I just finished freshman year in college, but i moved in the middle of high school. so some of you are actually lucky for having experienced the best two years of high school, when i had to struggle to make new friends because being independent in high school isn't exactly the popular thing to do. So I've had this loneliness feeling for a while now...
Here are some of my tips:
1) I try to keep in mind that good friends take time to make. i would really rather have those than good acquaintances. Focus on your study, it's better than focusing on being lonely. But sometimes it can't be helped. when you're starving and on campus, the feeling of sitting at a table by yourself is not comforting at all. But remember! There are lots of others who are sitting alone too! No one is looking at you and thinking you are some sort of loner.
2) be open to different kinds of people. No one can replace your old friends... because no one but them exist!
3) invite others to a school event or something. This part has been very hard for me because of my parents. They don't like me staying out too late/going to places by myself/ living life. I also commute, so that just adds to the trouble. I see people becoming very close friends to their roommates or dorm neighbors, and i can't help but get a little jealous.

4) Clubs are pretty helpful. But make sure it's a club you enjoy, other wise you don't really have much to talk about with your fellow club members.
5) When you pass by people you've met, say hello, make some small talk. If you see that person on your way to class, there's a good chance that you will see that person again.
6) Class buddies are nice, especially in note taking classes, such as labs and recitations(prelab discussions? basically a class that's a waste of your time!). If they are your only source of a social life so far, at least it takes the ease off your lonelier times later on, so you can focus on your studies during that time, and not worry about being lonely.
I can't think of anything else, but i'm sure there are lots of tips. I'm just trying to list situational tips and such. I wrote a lot, but that's because i think depression is a pretty big issue in college. Having friends in highschool covers up a lot of stuff, because we have friends! They accepts us and all that. But in college we are sometimes more insecure.
Depression doesn't have to be because of loneliness. People are upset about their grades, relationships, weight, etc.
I wish for everyone to make some friends soon, and if not soon, in the next semester. Loneliness sucks, but at least it's not the end of the world. we can always make new friends.