Little one...if you do have an eating disorder it can become very dangerous for you. Hopefully, that's not the case.
If dancing is your passion and you want it to be your profession, REMEMBER, you need strong bones. You have to nourish your bones by following good nutrition. It won't make you fat, but it will promote good muscle health and strength, and give you good bone density.
When you don't eat enough, your body will take nourishment out of your muscles...then your muscles will begin to shrink, and your bones will become weak and brittle. They will break, even if you step off a sidewalk. A weak body is a target for any kind of infection, as well.
Your leg bones could become infected, and you will have to have surgery or it might kill you. At the very least, it will cripple you.
This is just a small part of what could happen to you if you don't treat your body well, so please listen to the wisdom of those concerned about you.
Sometimes people think that tough love will influence another to change harmful behavior, but until that other person admits they have a problem, it doesn't work. Your friends are suffering too, from worry for you, but they don't have enough experience in life to know how to positively respond to you...except to fight it or be critical of you.
It begins with you...and it's a simple choice. LIFE or DEATH??