>>/32887/
It's not about the reasoning, it's about the hidden message that she has no power over you, she can't tell you what to do and what not.
You want her to stop nagging you.
Well living things stop a behaviour if they get negative feedback and see that what they do is useless, when they see their pursuits not just backfired but were futile.
But living things not just learn to stop things but they learn what to do via positive feedback. In many cases they learn it by trial and error, however with intelligent beings one can present them the the alternative, expected behaviour which leads to result and positive feedback which reinforces the behaviour. This is how training of dogs happens.
So for example after on an occasion when she weren't nagging you, you could make a gesture and tell her she did good. Make her feel pleasant. After a couple of occasion she will seek this pleasantness and she will connect it in her heda that not nagging and feeling good is somehow connected.