My response to her was:
When you start to give yourself value for the real things rather than the things the world would judge you for, you start to notice those things less. I hear negative self talk from many (not all!) of the women around me and it makes me feel sorrow for them. So beautiful! So kind! So generous! So self-less! So creative! So, so, so full of beauty that it brims over into other peoples' lives and blesses them, too. They stand there, beautiful and strong and GENTLE, and forget to be gentle to themselves. We already know the world will judge us as "fat", "flat", "pale", "masculine"; it should not come as a surprise to us. Instead, we should choose to label ourselves: "changing", "trying", "long suffering", "compassionate", and always, "beautiful". Don't blame others, change your view.
I would add to this: this doesn't just apply to being overweight or any of the more visible physical things people judge each other on. You, with no make-up, no tuck-ins, no secret support, no special lotions, no shaving, JUST YOU, are beautiful. Society's current views about what is more or less desirable physically have NOTHING to do with your value. Your children, husband, friends, family, all who matter, love you for all of the things you do and are. This also applies to men who struggle with self-image, just sayin'.