Here are the facts according to wikipedia:
By 1964 he was in a relationship with Carol Shepp, a model originally from Philadelphia, Pennsylvania; they had known each other at Annapolis and she had married and then divorced one of his classmates.<20><25> On July 3, 1965, McCain married Shepp in Philadelphia, Pennsylvania.<19> McCain adopted her two children Doug and Andy,<27> who were five and three years old at the time;<25> he and Carol then had a daughter named Sidney in September 1966.<28><29><30>
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During their time in Jacksonville, the McCains' marriage began to falter.<84> McCain had extramarital affairs,<84> and he would later say, "My marriage's collapse was attributable to my own selfishness and immaturity more than it was to Vietnam, and I cannot escape blame by pointing a finger at the war. The blame was entirely mine."<84> His wife Carol would later echo those sentiments, saying "I attribute more to John turning 40 and wanting to be 25 again than I do to anything else."<84>
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In April 1979,<77> while attending a military reception for senators in Hawaii, McCain met and fell in love with Cindy Lou Hensley, 17 years his junior, a teacher from Phoenix, Arizona who was the daughter of James Willis Hensley, a wealthy Anheuser-Busch distributor, and Marguerite Smith Hensley.<84>
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McCain filed for and obtained an uncontested divorce from his wife Carol in Florida on April 2, 1980.<27> He gave her a generous settlement, including houses in Virginia and Florida and financial support for her ongoing medical treatments resulting from the 1969 automobile accident; they would remain on good terms.<84> McCain and Hensley were married on May 17, 1980<19> in Phoenix, Arizona, with Senators William Cohen and Gary Hart as best man and groomsman.<84> McCain's children were upset with him and did not attend the wedding,<77> but after several years they reconciled with him and Cindy.<77><29> Carol became a personal assistant to Nancy Reagan and later head of the White House Visitors Center.<89>
Alexander, Paul (2002). Man of the People: The Life of John McCain. John Wiley & Sons, p. 19. ISBN 0-471-22829-X.
Feinberg, Barbara Silberdick (2000). John McCain: Serving His Country. Millbrook Press. ISBN 0761319743. p. 18
# ^ a b Alexander (2002), p. 92.
# ^ Alexander (2002), p. 33.
# ^ a b c d e f g Jennifer Steinhauer. "Bridging 4 Decades, a Large, Close-Knit Brood", The New York Times, 2007-12-27. Retrieved on 2007-12-27.
# ^ Some sources give the daughter's spelling as Sydney, but this is incorrect; see Faith of My Fathers p. 172 or Meet the McCain Family. John McCain 2008. Retrieved on 2008-01-03.
Dan Nowicki, Bill Muller. "John McCain Report: Arizona, the early years", The Arizona Republic, 2007-03-01. Retrieved on 2007-11-21.
Barbara Gamarekian. "White House Tour Leader Courted and Criticized", The New York Times, 1981-08-30. Retrieved on 2008-02-09.
McCain, Faith of My Fathers, p. 156.
http://en.wikipedia.org/wiki/John_mccain#Senate_liaison_and_second_marriage