I wish my co-worker would be replaced
Do you not like your co-worker?
She is too cruel to me.
I'm sorry that she's mean to you, but you shouldn't wish harm on her. Try talking to her about how her actions hurt you instead.
No, I want her to be fired.
I understand that, but it really isn't the best solution. If you bring in a third party to help you work out your issues, it will be better for everyone in the long run.