I want to separate from my sister

TL;DR – my younger sister is mad at me all the time over ridiculous things and looks for a fight in everything treating me poorly and being nice to everybody but me.

Hello. I’m a 27(f) living together with my younger 23(f) sister. We’ve been living together for the last 4 years. We’re quite different personalities. It’s not a bad thing, but this sometimes leads to very hot arguments between us. Her most frequent observations regarding me are that I’m slow and whenever I’m in the wrong I have to figure out myself what I did and fix that forever (her wish). She’s told me several times that I am horrible as a co-tenant and that she simply just doesn’t like me. Arguments are almost always her yelling at me over really ridiculous things. My only “requests” regarding her co-living behaviour is to to avoid leaving dishes and pots with moldy food in them and not yell at me as it just makes me very anxious.

I have to mention here that I’ve co-lived with other people (in student dorms, shared apartments with friends) and she has not lived with other people besides me.

A recent event got me washing the dishes that were at that point in the sink and I’ve noticed a pan with dried and moldy food which I just left there for her to wash it herself. I’ve told her I have no problem with washing and cleaning after ourselves if we both use the certain room or kitchen equipment. She’s got inflamed by what I said and told me that I only clean in situations that are to my advantage. I asked her what that “advantage” is because I really couldn’t grasp that statement. Her reply was that “I shouldn’t be the one to tell you that and you should figure that out yourself”.

I am not the best communicator as I find it difficult to tell what’s on my mind when it has a negative connotation, but whenever arguments arise and she yells I try my best to keep my cool and not yell back or react aggressively. Whenever yelling occurs I just go silent or go to another room which just triggers statement like “You’re stupid”/ “Can’t you hear I’m talking to you?”/ “Fine go to your room and ignore me”/ “Are you ever going to grow up?”. I never witnessed this behaviour directed toward any other person (her friends or her partner) and just makes me feel like she straight up despises me.

There have been a couple attempts to have our arguments mediated by our dad but they didn’t turn out that great.

One things that makes it more unbearable for me is that she’s always starting this rage episodes towards me when I have important things to do with my life which right now are working on my master thesis and learning new skills for my future career whilst all she does is stare at her phone (facebook, tiktok, youtube) from the moment she wakes up to the moment she goes to bed. If I reply I get slammed down, screamed at or insulted, If I ignore her the outcome is the same. I feel cornered and don’t have the possibility to move somewhere else…

She’s always nice when interracting with anybody that’s not me…

I love her dearly and I don’t want to have our relationship broken completely. I just wish for these arguments to over ridiculous things to be less frequent and less about ridiculous things. I don’t know what to do to have her less volcanic when interacting with me. I’ll be grateful for any piece of advice on this mattter.