Actress, author and singer Olivia Newton-John, 71, is battling breast cancer for the third time. "I'm happy. I'm lucky. I'm grateful. I have much to live for. And I intend to keep on living it," she tells "CBS This Morning" co-host Gayle King in an emotional interview at her Los Angeles home. Newton-John talks about her diagnosis two years ago and how, while the pain can be unbearable, her spirit remains unshakable.#olivianewtonjohn Subscribe to the "CBS Sunday Morning" Channel HERE: http://bit.ly/20gXwJTGet more of "CBS Sunday Morning" HERE: http://cbsn.ws/1PlMmAzFollow "CBS Sunday Morning" on Instagram HERE: http://bit.ly/23XunIhLike "CBS Sunday Morning" on Facebook HERE: http://on.fb.me/1UUe0pYFollow "CBS Sunday Morning" on Twitter HERE: http://bit.ly/1RquoQbFollow "CBS Sunday Morning" on Google+ HERE: http://bit.ly/1O3jk4xGet the latest news and best in original reporting from CBS News delivered to your inbox. Subscribe to newsletters HERE: http://cbsn.ws/1RqHw7TGet your news on the go! Download CBS News mobile apps HERE: http://cbsn.ws/1Xb1WC8Get new episodes of shows you love across devices the next day, stream local news live, and watch full seasons of CBS fan favorites anytime, anywhere with CBS All Access. Try it free! http://bit.ly/1OQA29B---"CBS Sunday Morning" features stories on the arts, music, nature, entertainment, sports, history, science, Americana and highlights unique human accomplishments and achievements. Check local listings for CBS Sunday Morning broadcast times.