I am in no way an expert on this, but I find it surprising that she did confess. I have noticed that people with personality disorders, pathological liars, borderline personality, etc.. usually stick to their lies and seem to think they can get away with it. Even when faced with obvious lies, they continue to blame others and continue to lie.
Maybe she has no discernable personality disorder and is just evil or maybe it is drugs. I cannot understand this at all. Her psychological evaluation will be interesting to say the least.
And as others have posted earlier, I am asking myself, why am I so surprised to find this in a female as opposed to male. Had it been a male, I would not be so shocked (if that is the right word). And I do know that women do kill; they just usually fit into some kind of category that I'm not seeing here...
At this point I'm going to have to attribute this to just pure evil.