I hate my body

So today at school this boy just randomly out of no where said i'm emo and fat. I dont care about the emo part but when he called me fat I told him "I dont know why your just randomly saying that. I already know im fat" and he said to me that he was just reminding me. But when i got home I just started crying. I know im fat and ugly or whatever but why did he just randomly say that. It hurts even more when its said out loud. Ive been fat literally all my life. I tried everything I could do to be skinny. I just dont know anymore. I'd do anything to be skinny even if its unhealthy. Its like my parents set me up to fail. Feeding me mcdonalds and fast food. I hate my body. I needed somewhere to vent but I didn't know where, now im venting to a bunch of strangers. I feel pathetic.