Found this while googling for something eloquent that my friend could send to another friend (who is trying to make her go hang out).
1) We don’t need alone time because we don’t like you. We need alone time because we need alone time. Don’t take it personally.
2) We aren’t judging anyone when we sit quietly. We’re just sitting quietly, probably enjoying watching extroverts in action.
3) If we say we’re having fun, we’re having fun, even though it might not look that way to you.
4) If we leave early, it’s not because we’re party poopers. We’re just pooped. Socializing takes a lot out of us.
5) If you want to hear what we have to say, give us time to say it. We don’t fight to be heard over other people. We just clam up.
6) We’re not lonely, we’re choosy. And we’re loyal to friends who don’t try to make us over into extroverts.
7) Anything but the telephone.