Hey Castorp,

It's extraordinary that SFN can be diagnosed by corneal confocal microscopy. What an advance in medicine.
I can't explain your malaise but have been following the work of neuro-scientist Andrew Huberman and the role of the neuro-modulator Dopamine in motivation and focus and I wondered if his work would resonate with you.

Controlling Your Dopamine For Motivation, Focus & Satisfaction - Huberman Lab

Best wishes,

Atty