Nocturnes for the King of Naples1978
by Edmund White
From Amazon.com:
A hauntingly beautiful evocation of lost love, Nocturnes for the King of Naples has all the startling, almost embarrassing, intimacy of a stranger's love letters. The intense emotional situation envelops the readers from the first page; like all images in a dream, White's characters are the most real people we know, thought they remain phantoms. Each chapter, each nocturne, is set in a different emotional key, but all are interconnected through such subtle modulations that the final effect is devastating.
— from OpenLibrary
5 editions at OpenLibrary