For starters you should contact the home office of the insurance company and speak with customer service and tell them what has happend and that you want to file a formal complaint with the company. While the police may not want to be bothered with your complaint what your exboyfriend is doing is a violation of the law; he is trying to extort money from you in exchange for not making a false report against you, (actually to be factually correct it would be extortion even if what he was going to report were the truth). After making your formal complaint with the insurance company where you identify his mother and her activities explain to them that you want them to take action against her and you might even want to consider terminating your policy with them. Then you should contact the state police and attempt to file your criminal complaint with them. If they refuse to take your complaint you can try to file it with the state attorney generals office. From what you have described I do not see where you would need to hire an attorney since it does not sound like you've done anything wrong; your ex and his mother on the other hand should think about hiring attorneys.
I agree with Mr. Pichlik. I might add that you may look at your state laws regarding civil harassment. A restraining order may be in order.
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