Well, obviously pray and pray. But, when I was with a girl. She had an eating disorder, and I helped her with it, by boosting her confidence, complimenting her a lot, telling her you WANT her to eat and that she does not look good if she DOES NOT eat. Just keep pushing good things and pushing the fact that you want her to stop and she will most likely. Be pushy like, act like she is crazy for thinking she is fat, and not eating, like " what you are not going to eat?" or "are you seriously throwing up? you are so attractive and fine the way you are I am shocked that you literally believe you are defected it blows my mind how someone so beautiful does not even see how awesome she is and is seriously believing she has to throw up or not eat"" All she wants is to feel good about herself, so all you have to do is keep making her feel good about herself and comfortable about herself and body. The girl I saw was throwing up, and I would get upset and be like no do not do that, and she saw that I cared and it helped her stop knowing someone cared that much that it hurt them. And I would be on her case about it all the time. "did you throw up again?" "why is their red in the toilet?" lol stuff like that sadly. But ultimately it was the fact that I kept pushing and insisting that she was perfectly fine the way she was, and since they brainwash themselves into thinking they are fat whether they are or are not, it works to kind of brainwash them instead of them doing it to themselves if you get what I mean. Not brainwashing but being that constant voice saying "you are fine the way you are" and "you are good enough" because the it counter acts the voice in their head that says otherwise. Just tell the husband to make sure he tells her how perfect she is the way she is, and how comfortable he is with her and how she should be super comfortable the way she is, just give her some super positive compliments all the time and give her tons of love and just let her see it in your eyes and your heart. It works. The girl, went from throwing up, to not eating enough, and then stopped all together. It was a process, but it stopped and it almost brings me to tears how beautiful it is to help someone with that struggle. But obviously only Christ can truly help us! Praise The Lord of heaven and earth!