My sister blew up at me, yelling with her face turning bright red because I was trying to help her figure out where a bookmark-size piece of black plastic had come off from her car.

She said “I opened my trunk after grocery shopping and saw the piece there”. She opened the trunk, gave me the piece, and then closed the trunk.

I was confused because, from what she said, I thought the piece fell off from inside of the trunk.

I said, “I thought the piece came from somewhere in your trunk?”

She said, “DO I HAVE TO TELL YOU EVERYTHING 3 TIMES?!” And points to the side of her bumper and says, “It was shoved in the corner of my bumper!”

At this point, I am crouching down to look on the outside of her car to see where the black plastic came from because I realize, by the look of the piece, it is from the underside of her car or wheel well. I say, “Oh, I thought you said you found it in your trunk!”

Without skipping a beat, she starts yelling like someone at the height of a fight, veins popping out of her forehead and neck and a red face. Like someone who has just completely lost it. Going on that she “ALWAYS has to tell everyone things 5 times” etc, “NO ONE ever listens to her”.

These fits happen almost every time my immediate family gets together and they can be aimed at any family member. Usually, the only thing one can do is to stop talking and walk away. It is really disruptive. My family hates it, it sours the mood and usually the source of her frustration is such a trivial thing.

I was trying to help her figure out where the plastic came from. Just moments before, everything was pleasant and fine. Then she started yelling at the top of her lungs at me because I didn’t understand the plastic came from the outside of her car.

I was so frustrated, I chucked the piece toward her from about 10 feet away. It hit her in the face. It was lightweight, so unlikely it could hurt or could have caused much damage. Then I went inside.

My father is near the end of his life with cancer, we have always called him “Dide” and our mom “Mime” or “Mimie”.

She came inside and starts crying and yelling some more and says she’s leaving, no one ever understands her, and this always happens. She says she called the cops and that I can answer to them because I assaulted her and I will likely be arrested. I can tell she is lying, and she immediately says that she actually didn’t call the cops. She asks over and over for an apology. If I apologized then, it would have not been genuine. I needed to cool down from the mental whiplash. Each time she yells and gets angry like this instantly, it always feels so out of the blue, such a disjointed reaction, and it is shocking. I get blamed for her “needing to leave” and I believe I ask her to please not leave.

I know that her reaction is likely due to her stress and is not directed at me, as it is always so abrupt and odd and doesn’t ever match the situation. Even though I understand the source of it, it does not mean it isn’t annoying when it happens and very frustrating to deal with. I always know she will blow up about something each time our family gets together.

I know throwing the piece of plastic was not right and I feel bad about doing it and frustrated at myself. Usually I can just kind of just swallow and just get away from her when she is suddenly flipping out.

She sent some messages that I responded to immediately when she arrived home to our family chat. Then, she messaged the chat with just me, my mom, and her. Then, I messaged her the next day in a chat between just me and her.

My mom says when this happens, we cannot change anyone’s actions, we just need to walk away. I agree, and mainly this is just me venting. These outbursts of rage over minor things are preventing me from feeling close with my sister. I find it mostly just really strange.

She does not have a partner, to my knowledge is not seeking one, she lives alone with her two huskies, has some friends. She could be on drugs, but I’ve been unable to get any clues into that besides my speculation. She has bad insomnia and has for her whole life. She has a good job, about 100k a year, but cannot manage her money, so is usually needing to get loans from my parents and me.

My sister overreacts and it is strange.