I don't believe that there is one word that can definitively say that "someone hates everyone else, but himself" because there is some ambiguity concerning how that person feels about himself. So now you are limited to words that describe someone who hates everyone else . . .
- Curmudgeon
- Asshole
- Grump
- Bigot
- Antagonist
The problem with these words is that not one of them clearly defines a person who unconditionally hates everyone.
I think this is an unanswerable question.
