My opinion is that she is too young for anti anxiety meds.
What she needs is cognitive behavioral therapy. She needs help to retrain her brain.
Right now she has a recording that keeps on replaying in her brain every time she eats. CBT will help her to play a NEW recording...one that helps her to calm down, trust, and know that she is safe.
I think that your daughter sounds like a perfect candidate for CBT and I'd work to find a provider in your area who specializes. Here is some more information: http://www.nacbt.org/whatiscbt.htm
*Disclaimer: I am not a mental health professional. I am an EMT and Combat Medic who deals with Soldiers with PTSD and TBI on a regular basis. Please seek guidance from a licensed mental health professional.