Okay. I can speak from experience, as I used to have my own ED. Although it wasn't bulimia, I still know what you need. I could get over mine quicker, but you obviously you have a deeper case.
If you can't stop by yourself, then you need obvious medical attention, quickly. First, tell your parents. Not your friends or a counselor or anything. Your parents. This will help the most since they're your legal guardians.
Go to the doctor. This is the only way it can be stopped. Eating disorders are mental diseases. But it can be cured with rehabilitation. Things like reteaching yourself how to eat. You also may need counseling.
Good luck, and I hope everything works out great. I'm sure it will. :)
-------
Somethings don't spell out right in life.
Fcuk.