Sister rant.

I'm so fed up with my sister! Where do I even start?! Everyday she wakes up and talks I feel like I have to tiptoe around her so I don't anger her. Then if I do anger her for some random reason she's mad at me all day! But if she's not mad at me for some dumb reason she's constantly bugging me and making fun of me. Today she asked to borrow a shirt. I said very kindly, "No. You took it last week without asking then gave it back dirty and with a tear in it." She flipped out! She started yelling how she was never lending me clothes again, I didn't react kindly either and we were just yelling at each other. Later when my Gpa came over I was quiet like I usually am when company comes over and my sister was all just like "Oh, she's just mad because I took her shirt earlier. She's being silly." that's not even what happened! I feel like she's constantly controlling our relationship as sisters, and if I try to take control or not play her games, she gets so mad at me, that living in the same house is terrible! I don't know what to do! Any time she talks to me I just get so angry about it all, I push her away so I don't have to deal with it. But I love my sister! I want a good relationship with her. I just don't know how to have one when she is a mean, controlling brat, who in my parents eyes, is a nice and mature woman.

i can see how the relationship with your sister must be very frustrating. I do not understand why your parents think she is so mature. Maybe you should record one or several of her rants. That is if you think your parents would listen!
I can only think ignoring her would be your best bet, although you say she will get mad at that too. But I think it may benefit you. Then go for a long walk and breathe deep!!! Try to relax.
Good luck