I actually like to think of it as a survival mechanism. (stay with me here, i know she's a zombie)It's her preditory MO. The hunters stalk, the big guys smash, the fast normal ones swarm mob mentality style,and she uses her frailty to lure food.I think maybe she does retain particulate memory, but just enough to remember how emotions effect others a.k.a food, so she cries to lure them. That being said, maybe she was empathic/psychic when alive? I don't know but I like to think of it sort of this way for some reason.