She's at ease in conversation. Relaxed, radiating cool. Body language: I am comfortable speaking with you.
Belied by her inner turmoil. Anxiety, anger, confusion. She smashes her iPhone against the wall, or throws it out the window, or drinks herself sick so that she's unable to leave her bed until late the next afternoon.
That contrast: the cool, the tumultuous.
Perhaps she's like me. In her gregariousness the presence of new people calms the demons, pushes them into dark corners where they can lurk but can't speak.
Or maybe demons are simply shy. That would make sense. In their shame and loneliness, wishing to be unseen.