The legal definition, in a nutshell,  is a willful attempt or threat to cause injury to another with the ability to do so and an intentional display of force to make the other party fearful.  Assault does not necessarily involve touching.  Battery, on the other hand, does.  But the touching must be either offensive or result in harm AND there must be intent with the conduct.  From your questionhere it does not sound like you intended to harm her only to get her attention.  If she files seek legal help. And next time it might be best to stay out of the matter given the volatile behaviour of his ex and her propenity to blow things out of proportion.  Good luck.