Advice on my life

I’m 19 live with my great grandmother my boyfriend also lives here with me. My 21 year old sister also lives here. I’m currently unemployed, I do have money saved though. My older sister honestly makes me want to die. It’s no longer just a “oh you’re siblings they fight when they’re kids.” It’s much worse than that. She rarely pays her car payment, which is under my great grandmothers name, so she is forced to pay it. My nana does her laundry, pays her bills, buys all the groceries. My sister even works! I don’t but I handle all my groceries and hygiene products etc. I clean the house every single day. She don’t clean up after she gets shit in the kitchen bathroom etc. her cat is basically neglected she don’t brush it or play with it barley feeds it. She walks so loud down the halls at night. I literally feel her walking through my entire bed. She slams every door every single time. I hear the microwave door shutting from in my bed room. It’s currently 2 am and I cannot sleep because she’s standing in the hallway smoking her door is wide open with her tv all the way up. I cannot sleep I cannot function. What do I do.... I cannot take it anymore and I feel like it’s pushing me towards suicide.