The Gracekeepers by Kirsty Logan
North lives on a circus boat with her beloved bear, keeping a secret that could capsize her life. Callanish lives alone in her house in the middle of the ocean, tending the graves of those who die at sea. As penance for a terrible mistake, she has become a gracekeeper.
A chance meeting between the two draws them magnetically to one another - and to the promise of a new life. But the waters are treacherous, and the tide is against them.