I am a law school graduate currently awaiting Bar results. I offer the following merely as general information, not to be construed as forming an attorney-client relationship.
1. If you do not mind changing your telephone number, try that. At work, ask to have your number block out hers. You can also block out her numbers through the telephone company. The police can put a trace on your phone for free or very little cost if you have a substantial claim.
2. One way to get this substantial claim is to contact your local legal aid society (found usually in the community guide section of your yellow pages, under legal services) and ask for the domestic violence clinic. This is what you do, you go down with all your thoughts gathered, all the dates you can remember of what she has done, when she has called, and ask the clinic to help you file a temporary restraining order against her, you then come back to get a permanenent one.
3. If you do all this and are successful, potentially you can sue her in court civillay for harassment and intentional infliction of emotional distress, possibly trespass if she has ever come onto your private property.
4. All these, especially the police trace, can lead to criminal prosecution, as well. That depends on if the police decide to arrest for any violations and how far the prosecution will take it.
Hope this helps.