There is no therapy to recover from Chronic Fatigue Syndrome. Even the cause is unknown to science to date.

I suffered from CFS symptoms for half a year. I used this time to read books, try lots of different interventions and recover eventually.

Here's my best guess hypothesis about cause & therapy:

CFS often starts with a normal infection. The same was the case with me in April this year. The infection does not cause CFS. But CFS develops in people whose immune system is incapable to fight off the infection. The body's defence is overrun and this leads to damage and CFS.

People with CFS have in one way or the other overloaded their immune system with stress prior to the infection. They did this by being in a situation one's body perceived as threatening to one's well-being for a very long time. So long that these people would be used to the stress so they would not be able to recognise the stress anymore.

The key to healing is to understand why the body perceives a threat and escape the stressful situation. This provides the body with the opportunity to recover.

Key literature I agree with: When The Body Says No by Gabor Maté, The MindBody Prescription by John E. Sarno, The Stress of Life by Hans Selye, "Dann ist das wohl psychosomatisch!" by Alexander Kugelstadt.