In His Sights by Kate Brennan (2008)

Subtitled A True Story of Love and Obsession.  Really interesting story about a woman who meets a man with some serious issues, falls in love, has a trying relationship, and breaks up with him. The second half of the book describes his relentless stalking she experienced from him. Her experience is pretty horrifying, but she tells it without a great deal of self-pity--despite having to even write this book under a pseudonym.