Most of the time, when people have this problem, it's cos they're afraid to
put themself out there & i know this is easy to say. but what i mean is, you gotta pluck up the courage to go up to someone and strike a conversation. Conversations can end quickly if you don't sustain them.. and by this I mean, ask lots of questions about their lives, their friends, their halls, their subject. Make comparisons with the stuff they're saying 'oh I used to have a friend who liked ____ ' 'Really? I've always wanted to do that'. I know this sounds wrong, but to make yourself interesting (if you're not), you can exaggerate or 'big yourself up' just a tiny bit.. i don't mean boast. i mean things like just throwing in things about your past experiences with ur friends.. 'me and my friends used to go to ____ and do ____ '. Make people think you have had experiences with girls/lots of friends in the past. 'Why do girls always take so long to get ready?!'
And the biggest problem with people like you (and me) I think, is that we're too afraid of sounding like idiots if we say something and 'getting rejected' if we put ourselves out there. Once that fear has gone, the problem disappears trust me.
You gotta become confident enough to say things, and talk to people, and the first step to doing that is accepting that your just the same as all the other people at uni. Just cause they've had conversations and sex with girls and you haven't, doesn't make them better than you or a different species of human.
I know the weirdest and most eccentric people who have finally made friends because they just put themselves out there. Just engage. Be curious about people. Be interested in something cool that you can talk about - music, sport, travel. It may seem like it, but it's not hard to get someone to like you. & most of the time, all this 'they don't like me' ******** is all in your head.
Good luck
xxx