That is why the idea that some of the most heinous things done to JonBenet were part of the staging, is something I find easy to accept. This is a woman with a Christmas Tree in every room, all public rooms beautifully decorated, and yet, feces all over surfaces, as madeleine pointed out dirty underwear on the floor and a basement that looks like things were, literally, just thrown in and stayed where they landed. This woman was all about what the outside world sees. So, I believe that once she saw how much damage the head blow had done, in fact may have believed JB was dead or at least could never recover, she set about performing the cover up.
Psychotic killer? I have never thought so. I don't think she deliberately did the damage she did to JB and I certainly don't think she ever killed anyone else or ever would have. However, I have no trouble imagining her going so far as "finishing her off" while rationalizing that she would never recover from the head blow anyway.
I also think she genuinely mourned her daughter. The drugged up, out of it mom we saw on CNN was real. It must have taken some incredible mental gymnastics to convince herself she had done the right thing, but I see her as one of those women who could do it.
That, however, does not preclude feeling the loss of a child I assume she loved.
There are some messed up people out there.