VIDEO : How Did John Lennon Really Feel About Paul McCartney?

The early 1970s were a volatile time for The Beatles. By 1971, Paul McCartney was in a place in his life that he would later call one of the "worst spots" he was ever in, claiming that "he'd almost had a nervous breakdown." A letter from John Lennon to Paul McCartney and his then wife Linda reveals how troubled the relationship was at that time.