I'm never hungry and have insomnia

I'm currently 12 and I have insomnia, iv done my research and I know I have it. My mom nor my stepdad care about my sleeping problems or me not eating. I'm simply never hungry. I'm not self-conscious about my weight   I used to be 85 l.b. But iv lost five pounds in three months, I have plenty of exercise. I eat one full meal a day and I eat 2 more snacks during the day I don't eat breakfast I'm not hungry in the morning  if I eat in the morning then I feel sick to my stomach all day. I don't know what to do. Please help, if it really matters I started my period when I was eleven. Thanks for any help! :)