I have had help with my fibromyalgia pain and sleep issues by taking LDN, low-dose naltrexone. I've posted more information previously on this support group. Here is an article about how LDN can also help chronic fatigue syndrome: https://www.verywellhealth.com/low-dose-naltrexone-ldn-for-fibromyalgia-cfs-716070
You have to get it from a compounding pharmacy and it's not covered by insurance. Mine costs $115 for a 3-month supply