I agree with you in part. There is no doubt that she is deeply disturbed, and the kitten was as a result of her rage. She has no guilt or remorse. if she’s not psychotic, or sociopathic... She’s in dire need of long term analysis and corrective treatment.
The real problem is that there are a LOT of people like her in the inner city. For her it’s cats. For others it’s peoples physical property or even people. This issue is far broader than what she did to a cat as much as the problem with the USSR was far more than just what Stalin did to the Jews.