The Undead, by Roxanne Longstreet Conrad
(writing as Roxanne Longstreet)

Most people avoid the cold and sterile halls of the hospital morgue, but Adam Radburn is different. He finds comfort in the fluorescent-lit darkness, peace among the still quiet, and safety in the undemanding responsibilities of caring for the dead. In fact, working as a morgue attendant is the perfect job for someone with an affinity for the night ... particularly if that someone is a vampire.

But Adam can no longer escape his past. He has killed for blood, but there is another who kills for pleasure and who wants only one thing: Adam's suffering and Adam's destruction. And in the world of the undead, the winner is not the one who lives the longest, it's the one who dies forever.