I hear you! My DH knows that I'm an I--he's seen me melt down if I don't get enough time alone! But EVERYONE else who has EVER MET ME would swear I'm an E, too, 'Neato. The usual response of people is, "YOU'RE an introvert? Nuh-uh! Really? Nooooo!"
Meh. I figure you and I are just proof-positive that "shy" and "introverted" are not the same thing.
I can talk to anyone about darn near anything (though 2 hours of talking about baby poop with strangers at a boyfriend's high school reunion was my limit...). I'm even good at the whole social thing.
But that doesn't mean I *want* to do it!

And I wonder if my kids are "fakers" like us, too! I'll definitely report back if I find anything I think will be useful.
