A woman broke up with him most likely on the account of another man. And the new relationship hasnt gone the way she thought so she wants him back, but he has been heartbroken and has just picked up the pieces.
Now, when he finally has relieved all pain and started over, been reborn, she seeks the old life and its safety, but he will never forgive her.
So she has to scream it till the end. That is not literally screaming, but the thoughts of what could have happened if they'd stay together.