The Oceanography of the Moon by Glendy Vanderah

Fate brought them together. Will their pasts tear them apart?
After the untimely deaths of her aunt and mother, young Riley Mays moved from Chicago to her cousin's Wisconsin farm. Here she found solace in caring for her extraordinary adoptive brother, exploring the surrounding wild nature and gazing at the mystical Moon-a private refuge in which she hides from her most painful memories. But ten years later, now twenty one, Riley feels too confined by the protective walls she's erected around herself. When a stranger enters her family's remote world, Riley senses something he's hiding, a desire to escape that she understands well. 
As the worst moments of their lives threaten to surface, Riley and Vaughn must find the courage to confront them if they're to have any hope of a happy future. With the help of Riley's supportive family, a dash of everyday magic and the healing power of nature. Can the pair let go of the troubled pasts they've clung to so tightly for so long? 
Like new, hard cover.