What's Gemma's problem really?

"Dealing with a food-addiction is serious business, and Gemma just isn't in that business. She is not a whiner, and she has a good grasp of the reality of what she is doing to herself. What she doesn't seem to be aware of is the "why". Eating and throwing up are the least of her problems, and that is what we as the readers want to know more about. I was hook after the first couple of lines. I can't wait for more. And neither can Gemma."