Can you explain how Sollux was "half dead"? Did it have to do with what his classpect was??

Sollux has always been the duality guy. He burnt himself out using his powers- But only halfway through, not all the way through. So he ended up half-dead- Except of course, ‘half dead’ is more than just an expression in Paradox Space, and he ended up literally just being half alive and half ghost.