I want to disown my sister
Why do you want to disown her?
I always get tired of her.
I understand that you don't feel very fond of your sister, but you shouldn't just disown her. Family is important and you may regret disowning her later.
What. I will just stay away from her. My life would be more peaceful that way.
I don't think you should disown her forever, maybe just interact with her less?