Lady Diana was "always the same person".
Shy, mis-understood, a young lady whom married a Prince, only to estabish, he loved someone else, a doting Mum, an advocate for things no one dared to do, using her position of power, a "lady"....
Whether she had an eating disorder or not is besides the point. She was forever beautiful, inside and out and as Jespah stated, she grew older and grew to love herself, in return, her beauty shone and her style of dress sense and hair / makeup was divine.
If only she was able to love forever.... Oh, she was. Through her children.