Anorexia girl: made a friend feel HORRIBLE =[[[ cheer me up, please?

So, I'm ana/mia and I was at a friend's house and she's kind-of chubby. She always talks about how I never eat etc etc and how she's so fat. I kept telling her she wasn't , which she really isn't--I think. So I told her to go check her BMI. Apparently her BMI is 25. So you can guess what happened. She started freaking out--I meanwhile checked mien and I am SO embarrassed to say that I'm fat enough to have mien be 20. GROSS. I'm working on a fast now. But this is about HER. So, she was crying I felt horrible. Then she starts eating all these cookies and I couldn't tell her to stop eating because... I just couldn't.

Anyone else with an E.D. out there ever run into a problem like this? What do I do? =[[[[[[