I have a food addiction and need help to stop (10 points)?

hi i am 13 year old boy. all my life i have a been a chubby kid and my parents would all ways make fun of me for it. when i was a little kid they would make me want to run to my room and cry. it wasn't till i was 9 i started getting dangourasly obese. when my parents made fun of me i would always turn to food for comfort. now i am 5'4 and 406 pounds. i currently have type 2 diabetes, high blood pressure and my heart is not beating normally. even now my parents still make fun of my weight. like last week i decided to relax in my hot tub and my mom saw me shirtless and said "jeez, you have bigger boobs than me, do we need to get you a bra." to be honest my 17 year older sister (who is skinny) has been the only person in my family who has never made fun of me and when my parents make fun of me she is always there to say "dont listen to them" and says "i still love you just the way you are." since my parents always call me fat i decided a good way to rebel was to keep eating. so for the past year i have been going to fast food restaurants 2-3 times a day. like yesterday i ate 2 large pizzas, a big mac, and 3 tacos right in front of my parents. after all of that i was full but i pushed my self to eat a whole box of twinkies and a family sized bag of dorritos when i was done i could see the anger in my parents eyes. i took of my shirt so my parents could see my weight gain progress and i started playing with my moobs and saying how mine are nice and big and hers are small and nasty it really hurt her feelings. now i dont so much eat out of revenge now i eat out of pleasure. i am addicted to food and i cant stop. i know what im doing is bad for my health but i cant stop my self from eating large amounts of food. its gotten to the point were i can barely walk anymore, and when a take only a few steps i get this raging pain in my knees. how can i stop my addiction.