That sucks the big one.
Similar thing happened to a mate of mine about three years ago, cops came to his work where is a factory manager to arrest him, as she claimed she had fears for her safety and he was being violent, which I know he wasn't, I have known him since we were kids, he would not hurt a fly, has not got a violent bone in his body, all the while she was rooting some guy she met on Facebook behind his back which came out later
Cops don't have a choice in the matter, with the Domestic Violence Legislation, if she makes a statement they have to put you before the courts, no if's no but's no may be's. Their hands are tied, most women especially the crazy ones know this, and will run to the police and claim Domestic Violence, cops then MUST by legislation apply for an AVO and if she makes allegation of assault they MUST arrest you and put you before the courts, it's a fucked system if you ask me.
Not the cops fault, but the laws fault.
Best start keeping track of everything in a notebook, ie if she contacts you, messages you, gets someone else to contact you, write down times, dates, and what is said and the circumstances.
If you did assault her, then well good luck, if not I hope karma gets her back.