Is it wrong that I'm not going to pay attention to this lady's stuff?
Do you think the lady is going to be mad or disappointed?
Yes, I think she'll be disappointed.
She should watch her own things, but if you agreed to keep an eye on her stuff, then you should continue to do that. You will likely feel bad if you stop paying attention and someone steals her things.
WTF, I'm going to sue her for shit. She should be happy I don't pay attention to her stuff.
You should keep an eye on someone's things if you say that you will. It's important that you are a reliable person and someone that can be trusted.