No one wants to be fat. No one wants to be skeletal. No one wants a life of lies and deception and isolation. The person with the eating disorder developed the eating disorder to help them cope with what they could not cope with any other way. This usually has to do with some kind of stress that creates unbearable anxiety .
Unbearable anxiety means just that.
The person cannot bear to experience their feelings, so the compulsive overeating comes in to numb them out. This could be emotional, physical, spiritual. I have an article I call the Number One reason for developing an eating disorder . It's about disregarding boundaries, i.e. disregarding where one person begins and another ends. However, please remember, not all people in such situations develop eating disorders.