What you describe sounds like there is inadequate insulation between floors. For example, you should have wall to wall carpet with underlay on your floor, not exposed floorboards.
Otherwise, the noise complaints sound unreasonable.
Regarding the comment which has been posted:
“if you feel her complaints amount to harassment, you could apply at your local court for an Apprehended Personal Violence Order(APVO) requiring her not to contact you except via a lawyer. Check that link for more details.”
An AVO is NOT warranted here. You will be up for a costs order and lots more anxiety than you are currently experiencing and you will cause unnecessary anxiety to this lady who does not deserve it. AVOs are not the knee jerk solution to problems in civil society, they were originally designed for people who fear being murdered.
Surely a reasonable person would attempt mediation about this noise issue before an AVO? Honestly.