Very sorry to hear such an inappropriate comment was said to your wife! Does the nurse know she has an eating disorder? Comments about weight, even if they're meant to be positive, can be so triggering. Do you think the nurse was saying it in a good way, as in she was too thin before? Or was she actually really saying "you're fat" --- to say that to ANYONE is wrong.
I'm glad your wife can share with you and I hope she's handling the comment ok. Hope she has learnt a lot in the classes and can maybe deal with it a bit easier than before. x