Excellent post. I was thinking the same thing about sociopathic persons and how, if you have never known one, it's very hard to understand that by nature, they adapt to whatever they think others will perceive as normal behavior with absolute ease. Most of them are so damn good at it that people who don't live day in and day out with them never notice a problem at all - in fact they are intelligent and charming and outgoing. But if someone or something is in their way, they DO NOT think of "it" as anything other than something to get rid of, even if it is a two year old child.
I heard a pundit on HLN saying that the problem for the state is that in order to get the murder 1 they have to convince the jury that Casey is a monster who would murder her child and I thought NO>>>>NO>>>> they have to convey that she is a sociopath and that she viewed a means to an end as just something that had to be done for her life to be better and that she felt justified to do so regardless of how heinous it may seem to you and me. And that's where all the lies lead as well - just something she had to do to get her way - and again, the reason she accuses GA and LA of horrible things, to garner sympathy and manipulate those around her to get her way and now, to beat a murder rap.
I have to admit, this is going to be an uphill battle for the state. It's not easy for anyone to relate to the socipathic personality, traits and capabilities unless you have some experience with them imo. Time and time again we expect them to understand "reason" or to "do the right thing" or "show some remorse", but they never do and they never will.
Edited to add: This is Mallory's problem. She is surrounded by them but she can't see it. She doesn't understand it. She still expects everyone to be normal when they are not. Perhaps even the A's a s a whole do not understand Casey and think she will finally tell the truth, see reason, be responsible, understand the errors of her ways. They are in for an eternal wait.