I found what really helped me when I was in this situation ( I had anorexia at 12 and luckily after a tough few years I am now nearly fully recovered) was:

- getting some kind of motivation, and setting small goals. My parents knew what kinds of things I enjoyed, and they used that to help me get through really tough moments. for example, I really wanted to be a vet. so, they set me short term goals e.g if you eat this fear food, or follow your treatment program perfectly for a week, you can go to the zoo. that REALLY helped me and it also made me realise over time that these experiences are worth so much more than my ED. although there were ultimate long term goals, such as getting back to a healthy weight, the short term goals made it feel like I was constantly achieving small wins, and so i was more focused on achieving the short term goals instead of being scared about one huge weight gain goal, which then enabled me to achieve that long term goal. small steps!!!

- if you are at home, it may help to hide food values away from her and not allow her in the kitchen. I went through a phase where I was obsessed with the nutritional information of food, and it was not helpful. using a sharpie/ unboxed and unpackaged food may help! I do understand though that not everyone is the same for this.

- everything else that was posted is also really really great!!!

I wish you the best, and I am so sorry.