I'm reading the posts and seeing Sunshine's struggles and want to wish you, Sunshine, all the luck as you battle this disease. It is a disease and requires a lot of work. I've had friends with this disease and it takes a lot of work and includes therapy.
For those who are struggling with how much to weigh, I emphasize getting a body fat test. I am 5'5 and now 50 years old. I started to gain weight when I was 34 and decided I needed to weigh 110 pounds. That seemed about right to me. I got my body fat test and it showed, at 135 pounds, I was at 24% body fat. So I increased my weight lifting and aerobic exercising and dropped to 121 lbs. I thought I was doing well and needed to lose only another 11 pounds. I went back and got my body fat tested and was at 14% body fat. I figured out that I was never going to weigh 110 pounds and so I needed to change my expectations of what my right weight needed to be. Now, I was assisted in this by my knowledge of my weight when I got back from a cross county bike tour during the summer after my sophomore year of college - and I weighed 118 pounds. During the ride, I had also lost my period so I decided that 120-125 pounts would be right for me.
Everyone is different but for many people having some solid measurements about your body fat, your height, whether you are large boned or have more muscle mass than most, will help.
I've just started to ride again and can't figure out why, after 2 months I haven't lost any weight - so I think I should go back and get a body fat test to see if I am gaining muscle mass. Hopefully that's the case.
Unfortunately, for those who have eating disorder diseases, the measurements don't matter much so this probably won't help for Sunshine. However, I'm hoping you, Sunshine, will find something that works for you.