J.S.
V.,
This sounds very difficult for you. You must feel very helpless. Unfortunately, I suspect that going to a conventional psychologist or psychotherapist might just result in medication, without any real inquiry into the cause of the problem, or any real long term healing. You will have to decide if this is best for you and your daughter.
Food allergies are certainly a potential culprit. For an excellent local lab for the state of the art testing in this area, see www.enterolab.com. Even if you think you are "watching" what she eats, there could be things aggravating her like gluten (wheat, barley and rye), dairy, soy, corn, yeast, food colorings, additives, pesticides, etc. A good pediatrician who knows more than average about nutrition is Dr. Deborah Bain in Frisco, www.healthykidspediatrics.com.
My next comment may sound rather unconventional, but you seem to have a rather unconventional situation. Have you considered consulting a medical intuitive? These are people who read the energy field of an individual to determine the root cause(s), emotional and physical, of a particular problem. A very famous medical intuitive is Carolyn Myss. www.myss.com Another one is Barbara Brennan. www.barbarabrennan.com. You can read their websites for more info, although I don't think either of them do individual readings anymore since they are reaching a larger audience. However, a local practitioner is Dr. Rita Louise, found at www.soulhealer.com.
By way of further explanation, Chinese doctors also work with the "energy" system of the body through acupuncture. Western medical physicians can't figure out why acupuncture works because they don't learn about energy in the body. Read some research studies. They often end with the conclusion that "acupuncture works, but we don't know why!" If they ask the Chinese docs, the Chinese docs will tell them - it clears energy blockage in the body, which of course makes no sense to the Western doctor who only learned of drugs and surgeries in med school. They will then try to default to speculations involving the nervous system, which is of course not the same as the meridian energy system. It would be very painful if acupuncture needles were placed into the nerves. Ouch! Rather, they are placed into the meridian energy system in the body, which is why it is not painful. Energy study is a huge gaping hole in Western medical training, along with other areas like nutrition.
The good news is that some western doctors are beginning to understand energy and study it. For example, see www.harmonyfamilyhealth.org. Dr. Daniel Chartrand is a western trained, holistically minded, family practice MD, who is also trained in acupuncture.
So intuitive energy readings and energy healing techniques (like Reikii or acupuncture, etc.), can be very useful, particularly if you want healing rather than drugs. It takes more effort to go this route. If you choose the healing route, your daughter may be too young for acupunture. There are other energy clearing techniques that may work better for her. Another website to try is Emotional Freedom Technique, www.emofree.com, which some find very useful. She is probably old enough to learn these techniques.
Very often healing requires a combination of approaches: nutrition, emotional healing, supplements, etc.
You can use your own mother's intuition to lead you down the right path for you and your daughter! Good luck.