I don’t think you have any legal responsibility to actually deliver it to her. If she wants it so badly, she should have to come get it herself once you have gotten it out of your mailbox. So, I’d simply tell her, “once I get to my mailbox, I’ll give you a call and you can come get it”. I wouldn’t worry about making a special trip for her convenience though. This is all my opinion though, you might want to check with someone else about the actual legal end of things.

I think the onus on what to do with the package is on her.

She can contact the sender and get the address changed.

I don’t think you have to do a thing, except say that she doesn’t live there anymore and refuse delivery.

Just tell her she needs to come and retrive it herself , she’s lucky you told her and it’s on her to come and get the package , not on you .

Just write her new address on it and give it back to the post office. They are responsible for it.

“Return to sender” on it and back to the post office it goes! She can deal with the sender and her lack of attention to detail without you having to deal with her. Not your problem.