If you like psychological thrillers, maybe check out "The Collector" by John Fowles. It was a really fascinating and enjoyable read.
From the book description on Amazon: tale of obsessive love--the story of a lonely clerk who collects butterflies and of the beautiful young art student who is his ultimate quarry.
John Fowles told the story in the form of a personal journal which made it all the more powerful and interesting. In the first half of the book, the story was told from the clerk (kidnapper's) perspective and then in the second half, it was told from the captive's perspective.