I (F23) fight with my sister (F15) on a regular basis. She is my only sibling and we do not like each other at all. I had to look after her a lot when we were younger because both my parents worked and have been butting heads since. She has been pretty rebelious since she was young and has always had a nasty attitude towards me, and so, I haven't always been the nicest to her.
She absolutely never listens to me and always says that I am not her second mom, and that she doesn't have three parents, which I agree with. Except that she uses it when its not necessary, like when I'm trying to tell her to do things so that my dad doesn't loose his temper when he gets home.
I fight with her the most though over cleaning the kitchen and her taking my stuff. She has started telling me what I will and will not do, which is unacceptable in my opinion. I am not allowed into her bedroom, even if she goes into mine, and I have to clean the kitchen, even if my mother has asked her to do so.
I have begged and pleaded that she stop's taking my stuff but she says that if I don't use it, than she can. Whether it's my makeup or clothing or even my art equipment, she takes it and fights if I try and take it back. She raises her voice so quickly, without me even doing anything, just to get me in trouble.
I found my expensive art equipment in her bedroom the a while back and brought it up in a civil way, but I was told to just leave it because it doesn't matter. I feel so frustrated.
I have started trying to ask my mom for help with these fights, and she will try and stop my sister sometimes, but most of the time I just get fought with and it hurts so much, as if nothing I do matters.
I overheard some insults on instagtam the other day, and my sister and I were fighting that same evening in the kitchen about her not doing what my mom asked her to do. She escalated the situation by deciding to fat shame me, something she does often. I am not what I would consider fat, but I am insecure about my weight, and she is super skinny.
I decided that I had had enough and decided to use an insult I had come accross. I said to her, "You know what sister's name, there is a tree somewhere out there in the world. This tree's sole purpose in it's life is to replace the oxygen that you waste, go find your tree and apologize to it."
It ended the argument really quickly and I won't lie, I was pretty happy with myself. My parents said that what I said made me am Asshole. It didn't seem to bother her much because she is unphased by everything, but I feel like it might have been crossing a line.
So AITA?
Edit: I live in South Africa and most people my age still live at home. Also found out that she ate my giant Reece's cups that I got for my birthday (which are kind of expensive here) and lied about it. This just happened, beyond over it.