There have been a couple things I can think of.
First was the flute. My mother bought a flute when I was around 12 years old, took a few lessons, and never picked it up again. Come high school I started playing it and found I was quite good at it so I took music all through high school, joined the flute choir, played in different music festivals etc. I ended up going to university to study the flute and took that flute with me as it was, at that point, pretty much my flute. I knew the weight and the tone of that flute, I knew it's nuances and personality. I dropped more money in getting the pads replaced than my mother did when she originally purchased it. Anyway, in the middle of my 3rd year of university my mother suddenly decided that she wanted to start playing the flute again and demanded that I return it to her immediately. I told her that I was in school and used it every day because that was my area of study but she would hear none of it and took it back, leaving me stranded without an instrument or the money to buy one. Someone I barely even knew ended up donating his old flute to me but it just wasn't the same. It was light and tinny and the sound of it was all wrong. I ended up dropping out of school that year for unrelated reasons but WTF. My sister told me that our mom never did once play that fucking flute once she got it back. At this point the pads I replaced are probably all dried and cracked and useless.
Another thing she got totally bent out of shape about was this stupid wooden dresser she'd made back when I was a kid. When I moved out and down to the city for university I lived in residence for my first year so I didn't take any furniture down. In my 2nd year I got an apartment with my then-boyfriend and my mom decided that I absolutely MUST take this dresser. Bear in mind I didn't have a vehicle or driver's license, my boyfriend didn't have a vehicle or driver's license and my mom lived a 4 hour bus ride north of us and her vehicle was broken down at the time, but somehow we were supposed to find a way to get this huge solid wood dresser back to our apartment. She refused to listen to logic of any sort and it ended up in this huge screaming fight where I was the most ungrateful whore of a daughter to ever exist and I was a shame and stain upon her reputation. My boyfriend and I ended up hitch hiking into town, staying at a friends place and catching the bus back to the city the next morning rather than spending another moment with her.
Wow, sorry for ranting like that.