I preferred the ending of the book, it seemed more in character for Neil. It also worked better with
the new occupants of Coach's house walking in on them.
It showed that what they shared wasn't something that could safely exist in the light, that it'd probably continue to be a source of shame for them, something they wouldn't want anyone intruding on. It dismissed the idea that they had experienced anything transfigurative by sharing their past, they weren't 'angels', and it wasn't a happy ending. They were now just more aware, in their own ways, of how awful it was that had happened to them.

Upon rewatching the film and reading the last four chapters of the novel, I change my mind.
The film wins.
Troll the respawn, Jeremy.