I saw it today whilst at the station and thought I'd remember the name to look up when I got home and now can't.
It looks like one of those pop-psychology books (so it could be crap?). It said something about being an exploration of how we think or something and used a fictional couple to explore the themes. It was in the Top Ten section even but cannot see anything similar on WHS site, Waterstone's or Amazon. Think there were 2 authors. What was it???