my ex-girlfriend had something similar, it completely stopped when she started jujitsu, she switched to wanting muscles to being skinny/having a hourglass body lol, and was infinitely happier, she was also happy with her achievements in jujitsu rather than her body, and i guess that’s a lot healthier, i don’t know if that can be helpful for you, i’m a man, having body issues isn’t something that i can relate, but i firmly belive that sports/martial arts, something for you to achieve/have a healthy competitiveness against skill rather than genetics can help a ton in that