Never Had One, Not Sure About The Whole Game

Well, the whole dating and girlfriend game is quite alien to me. i am 16, and live in the UK. I have a fairly large group of friends, about half boys, half girls. Strange thing is, pretty much everyone in the group has had a girlfriend/boyfriend, and most of them have 'lost it'. I don't feel isolated, as I'm good friends with loads of people. it's just that at parties sometimes, when I see everyone else getting off with their boy/girlfriend, and I am just sitting there watching with a beer and a cigarette. Theer are people also watching, as they too are single at the moment, just that i have never had a girlfriend. i'm not quite sure why. Partly it could be as I'm catholic (but not excessively so) so I shy away from the whole thing. I'm not some religious nutjob who believes in no sex outside marriage, just I am slightly scared by it all. I'm decent-looking. I'm not exactly Brad Pitt, but I have been scouted twice before (although I didn't take the offers up). Maybe it's also as I don't know how to tell if a girl is interested in you, as opposed to simply being friendly. So when a girl approaches me to compliment me on anything, I just say thanks, but don't dare to carry the whole thing any further. Money isn't a problem either - I play three card monte in Covent Garden, which makes me plenty of cash. I've wondered if I am gay, but I am always attracted to girls as opposed to blokes. The thing is, now I don't really seem to care abvout getting a girlfriend/losing it. Its all for the birds as far as I am concerned. but I don't know anyone else who thinks like this. does this mean that I am going asexual? Or gay? I really don't know. I'm not crushingly shy either - although I wouldn't have the cojones to try to ask out a random girl I didn't even know - yet I don't have the balls even to ask out a girl I do know. so what is it hardwired into me that makes me fancy girls, yet I don't seem bothered about whether or not I get a girlfriend?