I'm hearing an awful lot of whining from tattlers here who wanted Molly to gush in happiness over meeting them. Sounds like a case of sour grapes to me.
Personality wise, I don't think Molly is an extrovert like you all are expecting. Those are the people who can smile at everyone at the drop of a hat. Instead, she strikes me as an introvert who needs time with her own mind and would rather things be scheduled. (She can, however, put on an outgoing face and knows how to have fun.) I believe this due to the things she's said about preparation and the amount of time she spends reading for relaxation. I'm very similar to this. Catch us off guard and you will get a sour reaction for a moment as we adjust our heads to looking outside it and saying hello. It gets harder when the person approaching is filled with emotion and we need to size it up. The reacion means nothing but is so easy to incorrectly read as "get out of my face". (I've been told many times before that I act stuck up, like I'm better than others... in reality the opposite was always true.)
Did she actually say "Go away" to any of you? I doubt it.
Tattlers be tattlers.