Analysis of Friend on my shoulder

This demon beside me will never let me rest, he lives to torture me and put me to the test.

I'm really getting tired of his taunting ways.
  If you live to suffer why do you choose to stay?

I'm always by your side every waking day, but you place your faith in nothing as you waste away.

I won't be ignored, I'll jumble up your thoughts.
 I'll slowly break you down, then we'll see who's tough.

I'll never  let you rest, until your despair grows, then I'll bathe in your tears as they start to flow.

Let's see if you have faith of he who never speaks, or if you're wilted soul will soon succumb to me.