lightbrite- I myself am an ambivert, and I have a few good friends who are major introverts. They doesn’t go to shul on yamim noraim even because it’s too overwhelming for them.
I know for them, just like you are stimulated enough emotionally with very few friends, you should find one or two friends/family that you can talk/learn with a lot and that you feel comfortable with. You can hear over the phone and internet shuirs, or go to a real live speech and just try not to interact, but listen to everyone else and when you get home you can talk about it with one of your close spiritual friends.