Discombobulated

 I get discombobulated. That's what I call it.  Sorta like being depressed but not as black.

None of my usual distractions are appealing.  No reading, no TV, no hobby, no wander, no conversation, no snack.  I don’t feel bored, I just don't feel like doing anything else.

It's like having insomnia when you don't need to be asleep.  Except the internal thoughts are less interesting or coherent.  Camus style existential ennui? Perhaps.  It's annoying.

It's not cancer caused, I've experienced this longer than I've had cancer.  The disease might exacerbate it.

That's the thing.

No way to tell. Nor would it matter. 

Ennui is much better than abject despair, tho.  And I look good in a black beret.