There's many things that can be done here. Not only is it cyberstalking, but it is also harassment. Contacting the police with these issues does little or nothing. They are too busy fighting street crime. So, if you want this to stop, then I suggest contacting a few attorneys for a free consultation. You have several options. I wish you the best and hope that everything works out for you.
The response above is not intended as legal advice since it’s impracticable to provide thorough, accurate advice based upon the query without additional details. It is highly recommended that one should seek advice from a criminal defense attorney licensed in your jurisdiction by setting up a confidential meeting. Moreover, this response does not constitute the creation of an attorney-client relationship since this message is not a confidential communication because it was posted on a public website, thereby publicly disclosing the information, which is another reason to setup a confidential meeting with an attorney.
You need to call your local police department and report it. Also, make sure you document everything, date, time, what happened/was said/done, etc. If you are being represented by an attorney, call him/her and let them know what is going on.