Feeling Insecure, Needy, Depressed.?

I'm not sure if there even the right words, but everywhere I go and in everything I do I feel so self-conscience, everytime I see the boy I love's older, prettyer friends I always feel they're laughing at me, hating me. When people be nice to me I don't belive them. If a boy asks me out I think its a trick to get at me. I'm in love with a boy and I litterally stalk him. I know everything from where he sits after eating his lunch to what time he leaves school. I'm obsessed. I feel down most of the time, but occasionally I'll get wild, happy feelings. I don't sleep. I either eat constantly or not at all. I get angry and bite peoples heads off. feel like nobody cares. To my parents I'm the perfect daughter, with top grades and no troubles. To my friends I'm the crazy, depressed, fun wild one. To me? I don't know who I am anymore. I'm just sick of life. Everyday is the same. Life has no variety. i want happiness and excitement. I have nothing. No life, no friends. whats the point?