How do I begin to "like" my step-daughter?

I love my step-daughter because she is my fiance's child, but I do not like her and am happier when she is not around. She is a mini version of her mother and I truly know her mother, and not just stories I have heard second-hand. I wish she would go to live with her mother. I am not trying to be her mother, I just want the respect I deserve and not the attitude her mother tells her to inflict on me. It has come down to I am about to have little to do with her or for her or I am going to have to leave, leaving my soul mate because of this pint-size tyrant. Any advice?