People Of the Lie by M.Scott Peck. A must-read. He makes a very strong case that the most likely place to find evil is deeply into God's territory, where no one suspects enough to look. The Bible says to 'be wise as serpents but gentle as doves." There are definitely people who dropped the ball in that church to have allowed this to happen.
I find it so interesting that she didn't take into account how vitally important it was to her to have all these emotional ties to the people she was robbing before it was too late.
If she were really and truly sorry, she'd do the Zaccheus thing and doubly return everything she stole back to the church, instead of making them bring a civil suit against her to recover it. In fact, I know of few churches that wouldn't take her back in, especially if she confessed all to the congregation and asked their forgiveness. For one thing, they'd have to.