What the....?

I am not alone, but I am not with you.
I am not one person, I am a few.
Meet Verneilia my evil, and Vincent my rage.
Meet Vera, she's your rat in my cage.
I am not happy, I only love you.
But you have moved on, what will I do?
Vincent and Verneilia have combined as one.
Don't worry, it's only pure fun.
Pleasure from other peoples pain,
Will make you scream my name in vain.
Welcome to:...."relationships are a vicious cycle"
They hurt you, you hurt me.
You hurt me, I hurt them.
Does it ever stop...?
Only when I have you back!