Helena
I knew someone, many years ago, who had an eating disorder, like yours. As you know, the appitite doesn't return. But this woman sat down and after some thought, realised she really didn't want to die.
So, from that point, she decided to concentrate on the quality of what she ate, rather than the quantity.
It took her a while, but she sought out stuff that packed in proteins, carbohydrates, fats, salts and just about anything else her body needd, in relatively small quantities.
As others have pointed out, depression is a side effect of undernorishment, especially proteins and Iron.