Hideous Head-Chopping

I've built my little castle, Based on apathy.
And now I'm truly armed,
Against insecurity.
Stone cold thoughts,
Behind a grieving mask,
Furious eyes,
Analysing silly lies.
Ferousious grey mass,
Non-believing in a cross,
An aim so insane,
The last leaf must be slain.
A wood-chopping sound,
Goes in my head around,
The tree that once stood
Has now been chopped for good