51 years ago today, Irish singersongwriter Gilbert O'Sullivan released his iconic single Alone Again, Naturally, which tells a rather sad tale of a lonely man being left at the altar and then telling the listener about of his parents. The song connected with listeners on various levels: the downtrodden could commiserate with the singer, and the lucky ones who were not in this position were reminded of their good fortune. It sold 2 million copies, spent six weeks at the summit in America and earned him three Grammy Award nominations. It was the second bestselling single of the year in America behind Don McLean's "American Pie." Theories about the biographical meanings of the song have been around ever since, so today we take a look at the story behind one of the most famous songs of the 70s.