Eric Brown 
New York Dreams [EPUB ebook] 

In a futuristic variation upon the modern detective story, we follow Hal as he returns from retirement, seeking the answer to the mysterious disappearance of his ex-girlfriend, last seen with a child prodigy and an unknown older man. We accompany him during his encounters with the jaded individuals who now occupy sullied Manhattan, and share his anguish at the gradual realization of the devastating effects that Virtual Reality is having upon his fellow citizens, rapidly losing their abilities to interact in the real world.