Why can't I find a job?? I'm getting depressed.?

I've been out of college for two years now and I still work at the same restaurant I worked at throughout high school and college. I feel like that job being my major experience is holding me back. I am starting to wonder why I went to college at all. All I want to do is get a job where I can help others but fast food seems to be all I can get. I have a BS in Sociology and I've done two internships with a small nonprofit. They didn't have the money to hire me. That seems fairly common in this industry. I can't quit my job for a life as a volunteer. I have bills to pay. The thing about my degree is that I'm honestly not even sure where to start in the job search. I've been applying at restaurants, for office jobs, nonprofit jobs, and anywhere else that even remotely matches my experience. I am starting to feel like a failure. I'm losing motivation. I have had very few interviews. It's starting to make me sick to clock in every day. I guess I measure my success by what job I have. I need help! What can I do?