Have you read Rosario's review (http://rosario.blogspot.com/2006/02/danger-calls-by-caridad-pieiro.html) of Caridad Pineiro's series romances about vampires? There is a human-vampire couple (h/h of the 1st book of the series) who appear in the second and third books of the series, and how their relationship will turn out, since she'll die long before him, hasn't been signalled yet by the author.