This is so me. Completely from head to toe. It is true, extroverts ARE exhausting to be around. If I had a dollar for every time I wanted to explain to some chatty cathy that no I'm not bored, I have a book, that is my entertainment and I prefer it to listening to you babble, I would be a wealthy woman.
I think the best line is "..., after an hour or two of being socially "on," we introverts need to turn off and recharge." This is why (to bring to to the hobby) I don't see a lot of people. I spend two hours with someone, fully interacting with them, and I NEED to be left alone or I get super cranky. It is physically very tiring sometimes to be social, and actively social, for long amounts of time.
What can I say...I'm a loner Dottie, a rebel.