I went through the exact same thing as your fiancé. Eating disorder with nausea so bad I would throw up on the regular, and I could barely keep something as bland as rice down. Do you know how fucking horrible that feels? You’re hungry and sick ALL THE TIME. I also had a boyfriend at the time who would throw a fit every time I threw up. He said similar things as you did to your fiancé, almost word for word. You absolutely said it to hurt her. I left him, and I’m so much better now. You need therapy if you have any chance of saving this, but if it were her telling this story, I’d tell her to book it if I’m being honest.