Ex Girlfriend Harassment Steps

On the night of Saturday May 18th I had gone with * friends to Ocean City Maryland to car show. While there I saw my ex girlfriend who I had to cut off contact with 5 months earlier due to continuous attempts to get back with me and harrassing behavior. In a effort to avoid her seeing me I hid behind a truck that was parked close to were i was walking. She had seen me and her and her friend snuck up behind truck and began verballly making comments while hitting and pushing myself and my friends. We were finally able to get away and enjoy our evening. While walked back to my car to leave later in the evening we again crossed paths with her at which time she began to harass myself and my * friends her friend also joining in. She repeatedly hit and pushed myself and my friends eventually picking up a bottle but not using it. I repeatedly tried to walk away only to have her continue to follow and push and hit me at some point in a attempt to get her off me I pushed her away and she stumbled over the curb falling on to her butt at which time her friend then came up and hit me again. A person in her party recorded the act of her falling but not anything else however will speak in my defense if necessary. In the days since she has repeatedly told people that she injured herself while hitting me, but has texted me threatening to ruin my life and stating she has the video as proof. I have friends that can attest to the fact that she hit both myself and them and the party that recorded the video that was in the ex's party is willing to state that ex and friend where accosting me when fall happened and that the ex told her the injury occured when she hit me and not when she fell. What should I do?

Okay thank you