This is a tough situation for everyone involved, but your wanting to help is important in saving her life. It is very important to diagnose and treat eating disorders as soon as possible. At first, eating disorders are often difficult to detect, and teens usually make excuses or deny having a problem or needing help, just like your friend does. But this is exactly when the problem needs to be addressed.
No matter how patient and supportive you are, your friend may not admit to needing help. This can be very stressful and discouraging for you, especially when your friend doesn’t listen. You may want to consider discussing your concerns with a respected school nurse or physician, teacher, coach, or counselor. Then they may be able to talk privately with your friend or involve a parent.
Ultimately, she is the one who must realize her eating habits are harming her health, and she may need professional
help in order to do this. Keep in mind, that the earlier eating disorders are addressed, the better the outcome.