My two cents but potentially getting her some support with someone versed in body issues, body dysmorphic etc.
They are finding a strong link between alcohol use in families and eating issues, and though I did not grow up in an alcoholic home my parents both did and for me it came out with eating, food, and unrealistic body stuff.
I got away with some of it with people not trained with it. Getting that support was really helpful to me (in addition to just general support).