Am i depressed? somethings not right.?

i can't concentrate on anything. i don't know what i'm doing in life. i think i've finally found a sense of direction, maybe, but i lack confidence. i have issues letting people go, even when they've screwed me over, specifically guys. a guy ( he was a friend since i was 5, screwed me over, we rekindled things, ended horribly again, yet i can't get him off my brain ever. i pretty much FB stalk him and try to ruin him, its ridiculous i think i'm insane i dont want to but i cant help it. (hes my next door neighbor and brothers friend too)) i sit around by myself half the time at college. i havent gone a week without crying in over a year. i get all panicky about nothing and am on edge at times. i really cant remember the last time i was happy for an extended amount of time. i didnt used to be like this. (im a college freshman)