Thinking without due cause?

I've got this lingering feeling today,
Need to make it go away,
Need to keep these demons at bay,
Telling them to leave but they want to stay.

They play with my mind,
Like it's just a toy,
Chewing away, wanting to destroy,
I need to keep these demons at bay,
There's a horrible feeling today.

It's the not knowing, the never will know what was,
Does it even matter? If it doesn't then am I thinking without due cause?

Because my mind plays tricks on me,
But that doesn't mean it's not true,
And it's been swept under the imaginary carpet. Why can't I just ask you?
Is it because it's just dismissed?
Because I know what you will say?
But that doesn't mean it's not the reason,
I've got to keep these demons at bay.