My sister is a real nasty person. She has extreme bipolar and is most definitely a narcissist. She’s all nice one second and then the littlest thing g makes her flip off. She blames me for everything and any time I talk to her or try to tell her that’s not true she gets extremely upset and starts going crazy nuts. She also is a pathological liar and is very lazy and dirty and likes to take credit for me being clean and productive. She is also bearing 30 but acts like a teenager. My mom knows there’s something wrong with her but sometimes I feel like she takes her side when I’m trying to stand up for myself. Her and my mom also don’t get along, so I think she just does it to keep peace but nonetheless it’s still frustrating and my sister needs some psychiatric help but she refuses to see she’s a problem