Spoiler alert: if you haven't read this book and want to - don't read any further.
The St. Mary's River is pivotal in this novel. It winds thru the story and is used as a metaphor in many different ways. So here's the end. Doss and his friend Bob had released Abbie's ashes where the river ends and they are talking. The first voice speaking is Doss.
...time does heal. Not like we think it does, and not like we would - from the front - but more from the back or side or someplace we can't see it coming. It bubbles up beneath and rises all around. All of a sudden I dried my eyes long enough to look up, look beyond myself, and discovered my pain had become the sinew that held me together. I stood on the bank, stared out across the vast epicenter of me and faced a choice - do I risk the river? So I (figuratively) cut the water, paddled out of my own black hole and discovered that the river was not one but many and like it or not, they all merge. Each turn, each bend, led to something beautiful, something whole, something worth remembering... And there in that river, I found the glue that connected the pieces of me.
Bob(He is a former priest who did some time for various "infractions" commited while serving his parish.) waved his hand back across the river. "After I got out of jail, I wanted a place to hide. Some place with no past. A short time later, I bumped into Gus and he befriended me. And unlike others, he didn't hold me against me. I asked him why and he told me something I've yet to forget. He said, "Once this water hits the ocean the sun lifts it up and collects it in clouds until they get full enough, the wind blows, nudges them back over land, where they empty themselves across the continent."
"The River never ends."
We climbed in the plane, Bob taxied, if you can call it that, and then he took off...
And so the story ends. Bob & Doss flying thru the air. Freeing themselves to find beauty and purpose in the life that was left to them.