Take heed fellow traveler...

For inside the mind of every man
There is a saboteur
Wreaking havoc in your head
Filling you with dread

This saboteur is silent
Only you can hear its voice
Pounding in your senses
With every single choice

Do not lock yourself away
With a scheming saboteur
Or place yourself within its path
Or attempt to cure it of its wrath

You may think to follow it a while
That selfish saboteur
A word of caution:
With every mile, room, and tile
The saboteur holds your very soul on trial

While you suffer from the stress
Of trying to be your best
The saboteur is the one who stirs
Giving you no rest

However...

If you still struggle to seek it out
Or make this picture clearer
To learn the face of a saboteur
You need only find a mirror