Family getting in the way 🙄😭

I’m overweight(almost obese) and i’m 14. Tonight my grandpa wanted me to get some fast food and I responded by asking if there were any vegetables at the house. He said no. (I live with him btw) Anyways long story short he got angry and started yelling at me saying I always cause a problem. I personally suffer from multiple mental illnesses and low self asteem is one of them.☹️ He knows I'm trying to lose weight and so does my aunt but not only does she continue to go out and buy a bunch of soda for me but they're always trying to get me to eat unhealthy. I've been struggling with trying to lose weight for the past 6 months and this is probably the main reason why ☹️. They both emotionally abuse me a lot and I just feel like a burden to everyone. My mom kicked me out of the house for reporting her to dhr for abusing me since I was 3, and my dad left and hasn't really been there for me my whole life so I feel like I'm the reason for everyone's problems. I don't know what to do at this point ☹️ I’m not allowed to cook so that’s not an option. I’d honestly rather just not eat at all.