what are the characteristics/lifestyle associated with someone being a "mad cat woman"?

[lottie]

It's okay to love cats but not so okay to be obsessive with them that one spends all one's time and resources on everything to do with cats. I think it's probably a sign of a personality disorder. Deep down there could be other problems.

[MiNapi]

Maybe it's someone who doesn't have enough social contact and as a result, is obsessive about things, cats being one of them.

Yes, they will appear eccentric because they don't know how to conform to the norms of most people as they don't have enough social contact with others.

In my opinion, it's more of a negative thing because people get overly obsessive over something may end up getting OCD which is basically irrational behavior that could lead to the person harming themselves.