I think I have things going for me- yet I can't get a boyfriend.?

All right, I am in college studying to be a clinical psychologist, can sing quite well (okay, I'll admit i will brag a little, but trust me I am no snob, I am very laid-back I just want opinions), am learning guitar, earn very good grades, work 28 hours a week. I am twenty years old, and I consider myself to be quite beautiful- I am chubby, but have been successful shedding my extra weight so far. I have long, dark hair, greenish-brown hazel eyes flecked with gold, and a flawless complexion. I also have recently joined Best Buddies international, am really into anthropology, and am a disability rights advocate. Yet I can't get a boyfriend yet. It is just so frustrating, all the guys I have met so far are total losers.Am I doing anything wrong? Thanks!