Did your doctor do any tests as to why you are still having blood.
With having a eating disorder in the past did you have good support, to help you heal emotionally.
Also getting the correct balance of healthy bacteria back into your system, Ie acidopholus, etc.may help(natural yoghurts)
Are you taking any antacids etc, if so these can upset your digestive chemicals.
fruit or vege Juices may be a little more gentle on your system, as with all foods, try to go for no artificial aditives, they can cause various problems.
(purchasing a homejuicer may be an option-then you know what is in your food)
YOu may be intollerant now to different foods, search the net ie coeliac.
My husband diagnosed ibs, i found having him take flaxseed oil helped dramatically. when he would get stressed the symptoms would start, with the burning, now when ever he gets a slight symptom he swigs a bit of the oil and he comes right. someone explained it once almost like a digestive migrane.
i got on this site lookign for info, have a neice with similar symtoms, been in hospital for a year, 17. She has been through a terrible time, not eating disorder but her body manifested the same symptoms.
i would encourage you keep lookign tillyou find an answer, your body is telling you it needs help, good on you for asking as you have obvioulsy been through alot. keep going.