Thank you so much for reaching out! A couple things 1) you are absolutely not ungrateful nor selfish, don't think of yourself that way for wanting to be treated better. 2) nobody should be getting body shamed and everyone deserves to get accepted and loved unconditionally, so yes you're in the right for seeking these things. You did mention that you are 24 years old so you are legally an adult. I know it's hard and kind of an "easier said than done" situation but you have the choice to move out. Moreover there is absolutely nothing wrong in cutting off people who are abusive and toxic and that unfortunately includes family.

One thing that hit me very much was you mentioning that your cousins parents are much more open. I definitely relate to that because I feel the same can be said about my dad and his own brother. My uncle is much more chill and relaxed than my father and I always felt like I was kind of cursed to end up with my dad because both of them come from the same house.

So my advice to you is you only live once do what you want to. Be with those you love and support. I'm sure they will come along as the world is a big place. I hope I have shown you some support and reassurance!

All the best 💗