Newman and Woodward met on the set of the Broadway production of Picnic but they didn't fall in love until they played opposite each other in The Long, Hot Summer (1958).
While a lot of actors strayed, James Cagney never once cheated on his wife in the 6+ decades they were together. Not even Merle Oberon's advances could persuade him. In his autobiography which was published in 1976, he says
"I married her in 1922, absolutely the smartest thing I ever did in the whole course of my life, and I am still crazy about this lady."
Not only is it incredible that they were married for nearly seven decades, they both became centenarians! Bob Hope died at the age of 100 and Dolores at the age of 102. What was in the water they drank?