IRREPLACEABLE

I'm something irreplaceable because I'm what you need
Dancing to the beat you make, following your lead
Thinking not for myself but with only you in mind
Letting go of what I know, leaving it all behind
Knowing what I am to you, yet here I always stay
Being the only person that you haven't driven away
I wanna run, I'm stuck in place
I turn around, I see your face
Devil grin, evil eyes
Peering back, hiding lies
Questions whirl inside my mind
Evil of the darkest kind