[xupybd]

Pretty much this.

Sounds like you are doing better than you think you are. I know CFS is making life hard but your feedback loops might be making it harder. If you work hard and feel like you are failing, that can lead to burnout. Sometimes you need to realize that you're actually doing great. Allow yourself the joy of working hard and feeling good about it.

As for brain fog. I find listening to Binaural Beats with noise cancelling headphones really helps me. Most of my brain fog comes from my inability to ignore the world around and get a good focus on. Distractions cause context switching, context switching causes my memory to get overloaded.

Lots of small breaks help too. Sounds like you're doing that. Small breaks are a good way to refocus don't feel guilty about taking them.