Parents constant bullying?

Basically, I’m really overweight, like loads. I hate my body and the way I look. My mum and her boyfriend are always on at me about my weight. They just insult me about it. I accept that they might suggest I go on a diet but they don’t, they make jokes up about my size. They are both very overweight as well but I try not to say anything back to them. I remember I once asked my mum what she liked about me and she said a few things and then said ‘you’re pretty’ and Lee scoffed and said ‘pretty ******* awful’ and my mum just laughed. And then my mum and Lee went into the things they hate about me. It was a very long list. I have started feeling guilty when I eat. I feel powerful and in control when I don’t eat and when I exercise. My dad has a girlfriend and he has pretty much left me behind and gone on to live his new life. He goes on holiday without me. Him and his girlfriend are normally okay to me. His girlfriend is jealous if he hugs me or anything but that is just her problems. My dad defends my mum and Lee as well so I can't go to him with my problems. I have wrote a question about my mum and Lee on here before. It hasn’t stopped. They are still as bad as they were then, if not much worse. Lee hurts me when he pushes and pulls me around. The other day I was in the bath and Lee knew but he still tried to come in. The door was locked luckily. He said it was because my music was too loud. Do you think it was alright for him to try to walk in? Do you think it’s okay that they bully me about my looks? Do you think I have a healthy relationship with food? What can I do to not feel so alone? I feel like I have no one. Thanks for answering. I’m fourteen as well btw.