How to cope with post-college depression?

I need to do something..I think I'm growing more depressive by the day. I'm just having a hell of a time transitioning from college to this whole real world thing, I guess. I feel like my whole life I was "something." I was a 3rd grader, I was a girl in the spelling bee, I was a girl on her high school's color guard, I was a college student. I always felt like I was "on track," and now I don't know what I'm doing. I always felt like I was doing what I was "supposed" to be doing, and now I feel guilty 24/7 because I always feel like, no matter what I'm doing, I should be doing something else, I just don't know what. I'm just sitting around my dad's house because I can't afford my own place trying to save up money so I can get out of here, and I don't really know what happens from there either. I spent the last 4.5 years of my life busting my butt to get straight As thinking it was going to get me somewhere, and it's not because my English/professional communications degree is pretty much useless. I'm 22 years old and feel like the best part of my life is over. I feel like a total and complete failure in life--others I went to high school with are already teachers themselves now and have gotten married and have kids and all of that, and I don't even have a boyfriend. I don't deserve one, either, I'm a really uninteresting person nowadays.