thanks for the replies. I am going to try to do some of those things, like talking to my therapist.

Unfortunately, my day just got worse...

It's my grandma's birthday celebration (her birthday was Tuesday). My mom and I wanted to give my grandma a slice of cake to take home along with other leftovers, so I said I would help. Then my sister immediately said, "SHUT UP. NO, I AM DOING IT. IT'S MY JOB," and she became aggressive/hostile even though I did nothing other than offer to help pack up leftovers. She started shooing me away with her hands, too.

To make a long story short, she said I was being "disrespectful" because it's obviously "her job" to do it "and it always has been." What the hell??? (She was texting on her phone and clearly "busy" with Instagram, etc..) Then she took the leftovers and shoved them into one tiny container, after I very gently told her to separate the food into different containers. So what did she do? Italian sausage, peppers, onions, strawberries, blueberries, and gravy, all mixed up into a pile of slop. I said that, if anything, is disrespectful. Then she was like, "Who gives a f***? She will eat it." I said to stop swearing in front of grandma and that that's not the point. Then I got triggered and I asked my sister if she herself would eat it that way. Then she told me to shut up, but i pressed her: "answer my question." She wouldn't answer and then told me to "f*** off" in front of our grandma. (She squishes her food all the time and thinks it's perfectly okay. )

Is it really that hard to be respectful to people and to the food they eat? I mean, the chicken was literally on top of the blueberries and mashed up because the container was small and she squished it shut. Why???

My sister is an incredibly selfish, horrible, disrespectful person. Ughhhh... She is such a b**** toward me. She is such an entitled brat, but my therapist said (in the past) that you typically want to handle the b**chy behavior at a younger age because it's harder to correct when the person is older and used to getting their way and getting everything they want. I think that is very true because my sister has only gotten worse.