@Lovejoy Ziotea sort of cares, but she doesn't like caring. She can totally be nasty to him, because he's just so
cheerful and it drives her nuts sometimes. Earlier on she would have been actively vicious, and tried to get him to leave her (and Rodion) alone, and she actually sees /him/ as childish and naive. Nowadays she's less actively unkind, but it's very much a "nobody picks on him but me" kind of a thing. I don't know about understanding him. I don't know that she does. But she does understand that he cares, as stupid as that is, and she's learned to accept that, and in a way she hopes to ensure he doesn't lose that compassion.
I imagine he's very aware of hre side of the mess that was that one guy she nearly killed. And all the others she injured. I can't see him being okay with her if he didn't know it wasn't deliberate. Even if she doesn't care, or pretends not to.