MWG - if the doctors haven't already done so have them check your B-12 and D. I went through about five months of all sorts of tests and finally a neurologist found that my Vitamin D was really low and because of my age they want the numbers to be higher. If I hadn't had the B-12 deficiency the Rheumatologist told me that they would have diagnosed me with fibromyalgia. (I had numbness in my hands and feet and a lot of muscle aches and joint pains as well as extreme fatigue.) After being on Vitamin D for about 4 weeks the symptoms disappeared. Also, check for Lyme's Disease...I have that as well but the Vitamin D made the biggest different.