See? You tear yourself down before anyone has the opportunity to do so, even in a venue where we have no context so even if it WAS an exaggeration for you to say that we would never know.

What happened with that? If you were supposed to be paid you should demand to be paid. People will take advantage of you if they can. You don't have to allow that. Even if you have $50 million if you put in the time and were supposed to be paid, you should be paid unless you decline it. You're devaluing yourself when you allow people to take advantage of you.

People want to be around you, and want to choose you for things if YOU want to be around you. You're talking about how they didn't want you for the chamber orchestra and various things where people with less talent and experience are chosen but that's likely because those people sell themselves. They're confident, they may make a case for themselves, I get the impression that you would say "ok" and then use it to back up your low opinion of yourself. If you don't like you, no one else is going to either. Teaching at a collegiate level is highly competetive and if you go into it thinking you won't get a job then you're going to prove yourself right. The only thing limiting you as far as I can see is your own attitude and beliefs about yourself.

Yes networking plays a part, but introverts get great jobs too. No one in my family works in my field. My family is not well known in my city. I hate networking, I despise small talk, I'm socially kind of odd and different because I was homeschooled K-12 so I'm just not used to interacting with people constantly. I would rather eat nails that go to an event and talk to a bunch of people I don't know, and mostly I don't. I may push myself to do it more when I have to, but no job I've had has been based on who I know. It helps but it's not a necessity. Confidence will get you much further than talent though, it sucks but it's true. That's why people who are less accomplished and less talented than you seem to always do better than you, IMO.

Luckily, it is not magic. It is a skill that you learn and practice and develop. I imagine that you have, over time, become more and more skilled at music. That took time, and practice, repetition, making mistakes, recovering from those mistakes and trying again, etc. This is how any new skill you learn works. Confidence, self-esteem, that's all stuff you can learn and practice and become better at, but it's not magical. It does take effort, it's difficult, and it will feel like you are being completely fake at first. However you're not happy with what you're doing now so perhaps trying something new will help.