The Best of All Possible Worlds by Karen Lord
A proud and reserved alien society finds its homeland destroyed in an unprovoked act of aggression, and the survivors have no choice but to reach out to the indigenous humanoids of their adopted world, to whom they are distantly related. They wish to preserve their cherished way of life, but doing so may mean changing their culture forever. Working together to save this vanishing race, a man and a woman from two clashing societies will uncover ancient mysteries with far-reaching ramifications. And as their mission hangs in the balance, the unlikely team—one cool and cerebral, the other fiery and impulsive—just may find in each other their own destinies . . . and a force that transcends all.