Six Years - Harlan Coben
So, I've now read several books of this genre and I have finally decided I don't particularly care for it.

This one in particular, which was written by what would appear to be a veteran at this type of story, was full of enough plotholes to render the whole story completely implausible. I would much rather have had the concept treated as a straight romance than a suspense/thriller.

Oh well, live and learn.