Ok first off Belial - you have something of the look of my ex fiance so don't insult your face as that insults my taste!
Secondly, I do so know how you feel, and let's get real: we know that whether or not you have a partner shouldn't affect your confidence, but we also know that in fact it does.
Also, you mention that you only know how to talk to women as though they are friends. Does this mean that you relate to them as equals? With respect? Honesty? That you listen to what they say? That you're there for them when they need you?.....OMG I think I'm in love! Hehehehe.....what I mean to say is that that is exactly the way you should be talking to them. That's what women actually like. Not necessarily all women, admittedly (you'll probably have to discount the impeccably manicured, never a hair out of place, always in the latest fashions bimbos with nothing to say - because quite frankly they are barbie dolls and all they are looking for is a Ken doll. Eeeew. Be glad you're not one of those, because what will be left of you when that face begins to wrinkle and the body begins to sag? However, it seems to me that you're doing everything right if you're looking to attract the Jennaflowers, Stephs, Loulabelles and Liliths of this world.
19 is a shit age. And other 19 year olds are pretty awful creatures too. Especially girls (note I said girls not women). It sounds to me, is that you've committed the crime of growing into a sensible, mature adult just a little bit earlier than those around you which is leaving you with a void of people to relate to. Don't worry - they'll catch up. You just need to believe in yourself that you're doing everything right. Don't go changing as it sounds like it's the people around you who need to do a little growing up, not you. In the meantime, continue to nurture your friendships with the women around you. Learn from them. Talk to them about their boyfriend problems and learn how not to be a meat head like some of the guys they're probably dating. Learn how women like situations to be handled, and most of all, learn how all women are different so that you treat them all as individuals and realise that there will be more than a few in this world who are good enough for the likes of a guy like you.
Take care, and PM me anytime if you want to talk. And sorry if you think this is all utter BS! LOL