You may want to renew your efforts to get a restraining order. Although the judge found she previously was "violent", the fact that she now comes to your new home seems to be extremely unusual and would cause fear of an attack. She has not business going to the new location stirring up trouble.
Document, document, document. Everything that this person does, note it and make sure you have witnesses. Video cameras of your home and its perimeter may be something you explore. not only can it provide protection it can be used as evidence against this person if they insist on coming onto your property looking for trouble.
Don't set your video cameras to record things that would otherwise be considered private, like focusing it or in the direction of a neighbor's window.
The above information does not establish an attorney client relationship nor is it meant to provide legal advice.
I can't see any potential problems so long as threats aren't made. It may, however, do no good or make matters worse.
The above is general legal and business analysis. It is not "legal advise" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
Feel free to send the letter, as long as you don't include anything that might be construed as a threat to do her harm. I doubt that sending the letter will do anything.
As the other attorney said, videotape and photograph this woman whenever she does this. Keep good records, including date and time. Then, after you have plenty of evidence, go back in for a restraining order.
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