Sorry to hear that Gidji. While I'm vaguely familiar with CFS, I don't know the finer particulars about it. Perhaps a very frank discussion with your doctor would help with what you can do to continue your work?
I do know that while I was undergoing chemo treatments this past spring/summer, I would have days that just feeding my horses was about it. It was like hitting a wall at times, and believe me, I usually don't stop or give in. Was very humbling for me. The days I had energy I did what I wanted and relished every moment.
I wish I had some advice to give you other than talk with your doctor, but I don't. Please know I'll keep you in my thoughts.
Is your doctor concerned that if you overdo it will take longer to recover?
Be the kind of woman that when your feet hit the floor each morning the devil says, "Oh crap, she's up!".