I'm 17, had binge eating problem since i was about 12!?

When i was 12, i remember thinking i was fat,so i dieted, but i was embarred so i didn't tell anybody, but i couldn't do it, so everyday i thought 'ok, i'll start tomorrow'' . I then binged, and let myself go, consequently this led to other things being 'let go' , grades, social life etc, and this has been everyday for 5 years!!!! and i'm in a right mess with no self esteem and i hate myself. I 've been trying to make goals like, losing weight, going out more, give myself a makeover, but the same thing happens, i make a mistake and i give up totally, EVERYDAY. i kept saying to myself.."youll have your targets reached in 6 months time and you can be happy," that 6 months turned into another 3 months , then when that time was up, i'd extent it again....I'm still stuck in this never-endng cycle. I also feel really guilty because noone knows, so its like i'm being dishonest all the time! I'd hate to think how bad my family would feel if they knew i felt like this. It really makes me feel bad that they are so clueless, but I can't talk to my mum because she's so unsympathetic and sees being sad as stupid and a weakness. E.G the other day she was like " young people who are depressed are so stupid, what have they got to be sad about?!"..etc. ... I just want to sort myself out!!