I flew with a female pilot back around 2008 and she would tell me about a stalker she was having a problem with. I asked her if she notified the police and she hadn't. She said that she was afraid that they would not take her seriously. I strongly advised her to do it anyway, but she didn't. Almost a month later, she found out that this stalker was able to hack into her Facebook account and he wrote all kinds of nasty stuff about her, all the while he was also pretending to being her. She finally went to the cops and they took a report, but never followed up on it because they told her that since she didn't know his name or where he was from, they couldn't do much about it.
This kept up for several more months and this stalker was able to get all of her personal information. He wrote all kinds of letters to her employer and also cancelled her credit cards and a bunch of other stuff. I could tell that she was scared silly, so I offered her to stay at my home until this issue either went away or was resolved. She said that she didn't want to include me in this person's hate mongering, but I told her that we would deal with it when we had to. She was assigned to the same airport as I, although we worked different days, times, etc. I told her not to worry because my wife would be there and together, they would be very safe. I also have video installed around the outside of my home, so that would make it even better if this stalker would come after her of be waiting outside.
She still did not want to come stay with us. All totaled, after 8 months of going through this mess with the stalker, the cops finally caught him when he sent her a threatening e-mail. They were able to obtain his IP address, which turned out to be his sister's house and they arrested him there. He was given 10 months of county jail time, but the judge told him that if he would repeat his criminal activity after he got out, the judge would make sure that he didn't see the light of day for several years.
She never found out how he was able to obtain all of her personal information. I thought that it was kind of scary that he could do this.