I'm also an introvert. I get exhausted when spending a lot of time with other people. One thing I've noticed though is that when I do spend time with people, I prefer getting to know new people rather than hanging out with people I already know. I guess this is some subtype within introverts, because the "stereotype" is that introverts have a few close friends - Instead I have lots of shallow relationships and I am terrible at keeping close friends because I never spend time with them...