"Retribution" is just that -- making people pay. Except it doesn't happen, but sets up the pieces to do so. The old Emily is back, and it's nice to see her again. She's always been here, but has either been slightly distracted or didn't know what was going on to the people around her. It's unfortunate that in order for Emily to get back to her revenge-y ways, there is a sacrifice, but it has to happen in the overall scheme of things.