Leaving my little brother

Hello dear people, i was here some years ago regarding my relationship and was helped tremendously (mostly by soulmate, thank you so much for that). now i returned because i am seeking some help with my living situation. 2,5 years ago my mother sadly died from cancer. She was living with my younger brother who was then 17 years old (turned 18 later that year). i am 7 years older, just so you know. I then chose to move in with him into their 42m² flat for a lot of reasons. i am going to tell you a little bit about that. first of all i moved in because he needed someone to be there, for very obvious reasons (he was/is still in high school, not enough money, no experience being on his own and ofc he needed some family around him, because the father is not/was never in the picture). we have an older sister,7 years older then me, but she said that it would be better if i do it(im not going to go into that right now-we had our issues because of that, but we resolved it, but she was single by that time, so no husband or boyfriend etc.) however, i left my appartment, which i was living in with my ex who moved out one month prior and moved in with my little brother. the room i moved in is a connecting room , which basically means no privacy whatsoever. i tried my best making it my home again, i bought new furniture to make "my room" more cozy and to create a little privacy, but it just didnt/DOESNT work. being there feels like sh*t, i need to be honest and say that. i myself moved out of there when i was 17, because it was such a small space and also, and thats the biggest reason, there is just some things that happened, that i needed to get away from. i never felt safe or really at home in that flat because my mom had an abusive boyfriend when i was a teenager, didnt live with us but terrorised the sh*t out of us, and he was a pro in gas lighting and all the narcistic things you can do, BUT never physical. it still was very traumatic for me. putting that aside, it was also the home my mother made and a lot of people will understand, that its super hard being there.. so, like i said, i tried my best with making it my home, but thats never gonna happen. i tried making it work with my brother, but we were/are unable to make a plan about cleaning or cooking or what ever. when one didnt want to do their chores, they didnt, i am also speaking about myself. so that created a lot of tension, frustration and so on. i originally have always had a good relationship with him, but this situation is testing it on another level and to be honest im not happy (surprise, surprise!)there. i feel like im being an aweful sister to him. i am still coping with everything that happened and i need to start creating MY HOME, a place i feel peace and secure and that not gonna happen there. i also feel like im being a sh*tty sister, to be brutally honest and its killing me; my moods are sometimes awefull and he feels it ofc.. im trying to be aware of that and think before i speak, but thats not helping me, cause i still feel trapped. the reason why im writing here, to you guys, is that i dont want to leave him, or better said, i dont want him to feel abandoned. he really didnt have an easy life. no dad (there are some things that he found out, that are not good), mom died when he was a teenager, etc.. and now (*pitty party mode on*) he has a crazy sister, who is not able to make it work and live with him. i feel sooo sooo sooo awefull thinking about that. the last information i want to give you is, that i had a talk with my sister yesterday (we get along well now) and i asked her if we could have a talk with him. something like a family meeting (we meet every week on sundays-its our family day). i asked her because she isnt that dramatic. she knows the situation but she isnt that emotional about it and i feel if i had that talk with him on my own, it would be to "heavy". she said yes and that we should see how he feels about all of that. but i would really like some input from you guys, since thats something i came up yesterday and im still a little insecure about all of it. id like him to have a positive attitude about living on his own (since he is in the right age, where kids start moving out-he will be 20 in november and is still in high school-> we live in vienna) and when it comes to me speaking to him on my own, i think i would have all the feelings if frustration and tension in me, i wouldnt be able to talk to him in a "chill" and light way .. thanks for reading guys!