Me: no thanks, I'm going there later to do some shopping myself
Aunt: But we could combine trips! It's wasteful to both drive there on the same day! The responsible thing to do---
Me: ok, I give up. Please get me cat litter and cat snacks.
Aunt: Ok!!!! :)) Which ones? And what isle? What color is the package---
Me: exasperated Are you serious? I caved and gave you what you wanted. Now you're asking for more information? I told you I wanted to do my own shopping, and you fought me on it. I'm making a peace offering by giving you two items to buy for me, and you're saying I need to go find the names and package colors and isle numbers? Please just be satisfied with what I gave you.
The thing that she wants is to feel good about buying me something. But I don't want that. That's the disagreement.
I imagine most people would see me as the asshole here: she can't buy the right item if I don't tell her what it is. But I clearly don't care about those details; if I wanted something specific I would have told her that. The only reason I mentioned them was to appease her. I'm giving her something she wanted, something I wanted for myself, and she's demanding more.
I don't know all about your relationship. Looking at this situation in a vacuum, I think it was kind of her to try to be sure she can buy the right items for you. You didn't match that kindness. You could have, in a more neutral manner, told her that you don't need anything specific and that anything from the section will do.
You to have a skewed outlook or some bias. A person offering to save you a trip is a kindness, you seeing as "giving her what SHE wanted" is a very odd take. If all your relations with people are like this, then common factor theory points to you being the issue. Professional help can improve all those situations you may be dealing with.
All of my relationships are not like this -- that's why I've only ever posted about this one relationship. Where did you get that from? If reading comprehension isn't your strong suit, maybe you could reach out to your educational facility for a refund, assuming you paid for it.