I have been called a paedophile what can i do?

i have a grievance with a local women over a phone.. she has called me a peadophile on face book and then again infront of two other people last night. surely this is slander and lible. i don't want much done but it is the most spitefull and dangerous thing she could say. i want the police at least to give her a slap on the wrists? any ideas? btw obviously i am in no way a paedophile.