Previously, I'd just get frustrated if I needed more specific advice, because communication is exhausting, and learning is exhausting, and the combination of the two sucked.

This sounds like a challenging situation. How were you able to move past this in order to be able to ask for more specific feedback when you needed it?

I've found that it varies - if I have things down and just need to drill, I'll often be entirely content off in a corner repeating something mindlessly with minimal feedback (an occasionally "good effort, you will improve on this, don't worry" is very rewarding, but we're talking every 15-30 minutes)

You are very lucky to be content in this kind of situation. I wish I could be more content.

The assumption that just because I'm stuck repeating something a lot, I must need encouragement... tends to de-motivate me, because it says "hey, you're slow and abnormal and so I'm going to focus a lot on fixing you", which has a lot of bad connotations for me.

I think I almost have a good connotation around this kind of situation. There are at least two areas (singing as a strong example, and competitive swimming as a weaker example) where I started out pretty awful. I could have compared myself to the people starting out at the same skill level as me...but that would have been pretty pointless. Other people who were as tone deaf as I was at age 11 just didn't try learning to sing. So I made my reference group the people who were doing solos in my choir. After a few years, I think most people actually forgot that they had originally considered me "slow and abnormal." I started to get the comment "well, obviously someone with your natural musical talent..." Ha. Right. But I did succeed in proving, to myself if not anyone else, that if I put myself into situations where I am "slow and abnormal" compared to everyone else, I will make much bigger improvements than if I stick with the activities where I'm already stronger than average.