The Chronicles of John Zebedee — Elizabeth Schechter

Cursed with immortality, John Zebedee has resigned himself to spending the rest of eternity alone. Then he discovers an escaped captive in his barn -- the immortal heir to the Elven throne. Ethriel captures John's heart, and gives him hope for the first time in a very long time. But Ethriel's captors are hunting for him, and the rest of eternity may be closer than it seems.