I have a family member who has CFS and has also been diagnosed with mild Bipolar 2. I am learning more and more about this illness and its atypical traits. It's amazing how medical sites have generalized so many illnesses. I have definitely seen one manic episode 7 years ago and I believe one minor episode a month ago which did not result in insomnia but irritable, inpatient behavior. Problem is how do you differentiate a mild manic episode apart from just feeling better for a period of time? The same for a mild depressive episode. Could it just be increased CFS symptoms or is it Bipolar? If anyone has experience with this I would love to know. If you would like to reply here or message me directly, either would be helpful.