Us by David Nicholls

Douglas and Connie - scientist and artist, husband and wife - live a quiet and quietly unremarkable life in the suburbs of London. Until, suddenly, after more than twenty years of marriage, Connie decides she wants a divorce.

Heartbroken but determined, Douglas comes up with the perfect plan: he is going to win back the love of his wife and the respect of Albie, their teenage son, by organising the holiday of a lifetime. The hotels are booked, the tickets bought, the itinerary planned and printed. What could possibly go wrong?