Last night was a disaster

My cousin came for a sleepover yesterday. Am I happy? Definitely NO. Bt my sis seems to be happy.
When my mom asked her she kept saying 不知道. Dt is 'YES' for annoying-cousin-language.
My sis said she's starting to like her so she was super nice to her. She totally ignored my brother. She sort of make fun and embarassed him last nite. I was really mad at my sis bt I didn't show it. Bt no, dt doesn't mean I like my brother, it jz means dt I dislike my brother and I HATE my cousin.
My mom actually promised to bring me to Gurney yesterday bt then SHE CAME AND RUINED EVERYTHING.
We even planned to watch a movie at home till midnight, bt she came and ruined it too.
I wanted to do smtg in MY ROOM so I switched on the lights bt she complained so i have to SWITCH IT OFF.
So yea, yesterday was a disaster. SHE ruined ALL of my plans.