Vampires of Avonmouth by Tim Kindberg

Avonmouth City, 2087. Everything changes for David when a ship arrives from West Africa, carrying a vampire who hungers not for blood but mental energy. As she hunts those around him, David struggles to protect her ultimate prey – the woman he falls in love with, despite himself. For David is carrying his own monstrous secret inside. If he fails, she will lose her mind. Literally.