Need Advise on how to deal with a woman who uses the legal system like a revolving door?

On 11/18 I went to the local dog park as I do most Thursday mornings weather permitting). While I was there a woman ( has assaulted leashed and unleashed dogs with Mace) came in the park. I called my dog away from her and she said I was a "school yard bully" (mind you I have never met this woman but the other people there had told me about her and what her dog looked like) I asked her why she comes to the park just to cause trouble (from 30ft away). She came charging at me saying all kinds of crazy things including "your fat" " you should be home with your kids" (mine go to school) and kept following me and saying this weird school yard taunting (she is at least 50 and im almost 40). Then she starting yelling she was for the USA and Jesus and kept following me and the people I was with. I finally had one of the woman there call the police. they were there for 2 hours talking to this woman. they told us to stay apart yet the minute they were walking out the dog gate she came right over where I was and sat 10 feet from me. Then started in again with me and another woman who just came to the park 5 minutes earlier. I had to go down and get the police to cme back and they saw her approach me. After all this I got a paper in the mail today saying I have to go to mediation (I have not spoken to or seen this woman since that day and didn't even know her name till I saw the paperwork) as she filed harassment charges against me??