Nightmare

I thought I'd take a stab at poetry...Be honest in reviews. Also, this is a rondeau.

This shadow, born from the night,
Prowls near, always out of sight,
It waits for my lapse to sleep,
So my mind is free to reap,
And I become fit for fright.

In its world, it causes blight,
To courage, nerve, it makes slight,
If 'twere my choice, I'd not keep,
This shadow.

But though it may haunt and bite,
It leaves us all at first light.
Though in my thoughts it doth creep,
It's always kept far down deep,
For I will forever fight,
This shadow.