Will I ever find a girlfriend?

Heres my story: I'm 20 and in college right now, I have my own house and car. I am white, 6'5" and I've been obese for most of my life (weigh ~340lb now, with my height... yeah, big dude) and I've pretty much become 100% antisocial. Personality wise I'm shy/quiet, reserved, honest, independent, laid back and easygoing. I spend most of my time outside of school (cl/homework included) on my computer watching movies, browsing the web, playing videogames and I don't go out much (a good Friday night to me is taking shots alone playing videogames). I've never had a girlfriend or even been on a date, I have a few close friends but after 3 years of college I haven't made any new ones (they tend to go away after the school years over). The closest thing I had was meeting a girl I met online, she was cute and I liked her, we hung out like twice a week for a few weeks before my semester ended and we moved apart. She never really started texts etc with me; only responded to mine. We texted abit over the summer and planned to meet the first week of the new term, but she didn't come and I never heard from her since. Real depressing. Since then I haven't tried to meet anyone new, I feel that nobody would want to get to know me and so I don't make much effort to know anyone else. This whole things just depressing me more every day as I see friends/roommates/couples being happy and I can't figure out what I'm doing wrong. Is it purely my weight? I'd love to lose it but then I think... will this fix my problems or is it something else? And then I lose all motivation.