Sounds like she definitely might have something parasitic going on, whether it be worms(pin worms usually never completely cleared with meds), or something like yeast. I was the same way as a child and teenage years were a night mare until I started doing my own research and found a doc to do testing. I had a severe intestinal yeast infection, yeast overgrowth, and many food allergies including yeasts in bread. Most allergy tests don't show things like preservatives, dye's, etc.