I know several people who lie as a matter of course and what always shocks me is that they believe their own lies. I know other people, myself included, that can compartmentalize issues in their lives in order to deal with them. I was brought up to believe that lies were one of the absolute worse things in the world and I learned not to lie very young. So while I can compartmentalize things, I don't compartmentalize my own lies since I avoid lying at all costs.
(My husband was brought up to believe that people who told the truth were stupid, which was always interesting in our household, may he rest in peace.)
Please who believe their own lies AND can compartmentalize the more stressful issues in their lives are very dangerous, in my opinion. I believe KC has believed her own lies, so she reacts or is able to react to events based on her own version of the truth. How dare you say I killed my child - I did no such thing, etc.
We all compartmentalize or we would not be able to function in life. If we were not able to "shelf" our grief or horror, we would be not be able to move forward after these types of events befell us. Sociopaths and psychopaths take that compartmentalization to a higher level, unless they are the type of killers who love to kill and WANT to replay it in their minds over and over. KC does not want to do that, so she shelves it, compartmentalizes it, then believes her own lies that it did not happen.
In this manner, the truth becomes buried and the lie comes to life. She does not have to reverse this switch often because either people believe her and don't confront her or when they do, she switches lies until she finds one that they DO believe. Thus, the truth remains buried. The courtroom is no place for KC - there is no safe place, no ability to switch lies because she can't speak, and the more the truth comes to light, the more agitated she becomes. She may also truly be upset because she has compartmentalized Caylee's death so much that the reality of animals gnawing on bones and duct tape stuck to her daughter's matted hair that lies on the ground, separated from her head, clashes strongly with her compartmentalized image of her daughter in her whole body, playing with other children in heaven. So while the switch probably has not fully happened, some of the truth of the condition of her daughter has been exposed and her repressed feelings surface. I don't think those emotions include remorse or self-horror. I think they are the emotions felt by someone who now realizes what truly happended to Caylee's body.
So, remorse no - sadness, maybe. But not because of anything she caused, in her mind.
This is my opinion, of course, and I also believe that when the defense puts on their case, there will be a remarkable change of behavior in KC.