In EA she was much slower to open up and more guarded and defensive, i.e. more in character for someone who serves an evil goddess (enough so that many would try to kill her on the spot) and for someone who had been subjected to a less than loving childhood as part of a cult.
The hand situation -
it goes off whenever she has doubts or is shaking off the indoctrination. Her parents say it in another dialogue. I'm not sure if there's ever an explanation about why Shar cared so much about her - but it seems like she was going to be brought up as a chosen of Selune maybe, which would explain it.
