If your W has a high ANA count she should really consider seeing a rheumatologist. There are thousands of autoimmune diseases that cause chronic fatigue. I have SLE (systemic lupus) and I take a cocktail of drugs that are most commonly used to fight malaria. It alters the pH of my cells but I still feel the symptoms (massive fatigue, joint pain and blah blah blah). Essentially my cocktail is designed to block the overproduction of autoimmune antibodies. AI diseases are hell. The symptoms mimic so many other things and living with chronic pain is NOT easy. Not to mention the vulnerable state one's organs are always in. In my case my kidneys are "attacked".
CFS is an actual disease. I don't have it so I am not familiar with the particular treatment.
