Am I in the wrong? HELP

So my sister is 28 years old I am 22 years old I go to school full time and I work full time. I live with my mother and so does she. We live in a 2 bedroom apartment with my mom and dad my twin brother my sister her daughter and myself. Me and my sister got into the biggest argument this morning becauSe she's a slob and my mother want her to clean my sister doesn't have a job never went to school and sleeps all day but gets mad when I wake up in the morning to turn on the lights to get dressed since my closet is in the bedroom she sleeps in with her daughter and my twin brother. I sleep in the living room which I don't think is fair. She's up all night and she doesn't let me alwep because she wakes up to eat in the kitchen this morning I told her that she already stinks and it's time for her to put her big girl pants on and get her life together and move out and so what she needs to do to provide for her daughter. She got upset and she said oh you never travel I've travel Ed more than you'll ever travel and Granted I never travel last time I traveled it was a family vacation and I went to Dominican Republic in 2010 (I was 16) but ever since then I've held a job since then and I have been focusing in school because my theory is that once I get older once I finish med school I will be able to travel the world and back and still have money to pay my bills. She's like oh I know many people who live with their parents but I think those situations are different these people live with their parents and their parents have enough room in their house to have them. My parents accommodate her so they don't have to hear their mouth. I told her about the traveling she's gone traveling with many different boyfriends in the past and always comeback with no money. She left this weekend to Miami with a guy and came back and her phone got disconnected. She told me I'm 22 and I have no children so why the fuck can't I move out of the apartment instead of her. I'm leaving but I'm just sick and fucking tired that she thinks she's privileged. I'm sorry but I need to go to medical school and during those years I cannot work so why should have to move out when I don't have any responsibilities. If I was a mother and I had a child who needed me and needed her own space I would be working in mcdonalds if I needed to to provide for my children not sleeping all day and night she has no future for herself.