It can be. I also just thought of something regarding how bad.
I'm not suggesting this is the case with this woman. I still think it's a simple case of this woman not giving a crap about her kid, but regarding postpartum depression, it can become so severe as to cause psychosis in some women. At that point, then yes, the woman was out of her mind and didn't know what she had done.
But, that doesn't sound like that is the case here. It just sounds like this woman sat on her butt for hrs on end while her baby was neglected to death.