Hummingbird Salamander

This is a strange one, but I liked it. The main character becomes obsessively involved in investigating clues she is being fed by a mysterious, unknown person. It becomes apparent that she is an unreliable narrator - perhaps even a mentally-ill one - and that there is indeed something going on, but it's not clear whether it's what the narrator says it is. A number of quite bizarre and seemingly unconnected events eventually come together in a coherent, thought-provoking conclusion which is a satisfying, if not necessarily happy, ending.