A friend just sent me information about this. Cassava Republic will be bringing the writer Diana Evans to Nigeria on a book tour (three Nigerian cities including Aug 5th at Jazzhole and Aug 12th at Silverbird's Media Store).
I read her haunting book 26a a few months ago. The characters (especially Georgia) stayed with me for weeks afterwards.
There is a Nigerian connection, because Diana Evans is partly Nigerian. The protagonists of 26a (Georgia and Bessie) had a Nigerian mother and spent part of their childhood years living in Nigeria. I haven't read many books about mental illnesses, but this book deals with it in a very sensitive and engaging way.