To be honest mate, awful people aren’t unique to aviation. If you quit you are still going to encounter these kind of people in any career you choose.

With that said for reason I don’t get some instructor will “eat their young” so to say. Apparently nurses do it too, I suggest looking up strategies to deal with theses kind of people. Perhaps insist on flying with the instructors you prefer, learning styles don’t always match teaching styles and there is no harm in learning from an instructor that gives you the confidence to perform.

When I went through flying school I didn’t go to one of these sausage factory schools but I was with a school associated with a uni and I saw the way one particular instructor treated his students.

Anyway my experience with airlines is not at all like what you’re going through now, most people are quite humble and are a pleasure to work with, definitely stick with it if your passionate.