Send her to http://www.stopthethyroidmadness.com
and get her doctor to run all the recommended labwork, to rule out any thyroid problems. Since she has fibro, chronic fatigue, possible lupus, it is a very strong possibility that she's hypothyroid with hasimoto's thyroiditis. Generally speaking, having one autoimmune disorder sets you up to have other autoimmune disorders. My sister, for instance, has lupus and hashimotos. It's sad and amazing how many folks are suffering from multiple chronic illnesses that resolve themselves once the thyroid dysfunction is addressed.
She's also probably very deficient in vitamin D. Low levels of vitamin d can cause chronic fatigue, arthritis. When I got mine tested a couple of years ago, I was shocked how low mine was and when my brother got his tested, his levels were undetectable. He's just been recently diagnosed with hashimoto's thyroiditis.