Complex sentence: On 16 February 1951 Driberg surprised his friends by announcing his engagement to Ena Mary Binfield, née Lyttelton, the common law widow of Joe Binfield, who had died in 1948.
Split into simpler sentences: On 16 February 1951 Driberg surprised his friends by announcing his engagement to Ena Mary Binfield. She had been born Ena Lyttelton, and was the common law widow of Joe Binfield, who had died in 1948.