Yesterday I was watching a documentary about Karen Blixen, the heroine of “Out of Africa”, a movie based on her autobiography with the same title, and played by an unforgettable Meryl Streep. At a certain point Denys Finch-Hatton (played in the movie by the one and only Robert Redford) is mentioned as “the great love of her life” and I wondered about why is it that all great love stories – or most of them – have such sad …