My sister is 17 and still throws tantrums?

I'm 14, she's 17. And fine, she is kind of messed up in a lot of areas. She is extremely, extremely immature about most things. She doesn't act like she's 17. But one of the most immature things she does is she throws tantrums, and I am sick of it!

If someone says one thing she takes as rude, or my dad asks her to do a small chore (like cleaning up her OWN mess or helping cleaning OUR bathroom), she acts like it is going to kill her and she runs into her room, shuts the door, and throws a huge tantrum.

I mean like yelling, SCREAMING "I HATE DAD, I HATE MOM, LINLEY YOU'RE SO STUPID, WHY CAN'T YOU MOVE OUT, NO ONE LOVES YOU, F**K YOU, DIE IN HELL!!" near the window where the neighbors and anyone in our state can hear her. She won't shut up no matter what anyone says, no matter how nicely.

Her screaming upsets all of us, plus I am so worried that literally one day a neighbor is going to call the police, she is so loud. She makes it sound like someone is abusing her or something, but like today it was just because my dad asked her to clean up something before he installed her computer game. My mom gets worried about the same thing, and also it stresses her so much and she cries and fights with my dad.

My sister already causes so many of the problems in our house, and I'm sick of that, but I am so sick of her tantrums. They just kill all of us. Please, how do I get her to stop? Nothing anyone says will because she is so, so selfish. What am I supposed to do?