<human>: Can you condense the text into a few key points?

This boy and I have been together for 8 months, his older sister has never been overly fond of me. In the early stages of our relationship she would ask me a lot of questions and would just be really confrontational to me, I thought that it was normal and that once I'd been with him for long enough she would maybe warm up to me. But things haven't gotten better, and I often feel a bit intimidated by her. My boyfriend and I always get a long great but got into a fight for the first time a few days ago. We have since made up, but I guess she found out about the fight. He didn't tell her, so I don't know how she knew. 

But yesterday when I was at their house and he was in the other room, she asked me so what was your fight about? And I said it's none of your business, and she said excuse me? And I said your he isn't a child, you don't have any say in his relationships. She said he's my little brother and I have a right to know what happened, I said no you don't, why do you care, she started yelling at me, then I said ask him instead of getting mad at me you psycho, and my boyfriend walked in so him and I left. He has talked to her since and he tried to calm her down and stuff but she's pissed at me. I didn't mean to be rude to her or anything and I'm pretty much afraid of her so I'm surprised I was even able to say what I said to her. But now I don't know what to do or how to get her to like me? Did I fuck up? Or is it her fault? What should I do?
<bot>: My boyfriend's older sister confronted me about a fight my boyfriend and I had, I told her it wasn't her business, she said excuse me, I said her brother isn't a child and she started yelling at me.