The Washington Post has an interesting piece on the first Mrs. McCain (Carol) and John McCain's adultery with Cindy Hensley as well as other women.
It states that Mrs. McCain "endured much in more than 14 years of marriage" to John McCain. "She had raised their three young children alone while her husband languished in a North Vietnamese prison camp for 5 1/2 years. Her tribulations grew immeasurably after a near-fatal car accident that immobilized her for months and left her scarred for life."
By the late '70s her husband "engaged in what he later termed 'dalliances' with other women." And in '80, John McCain was deep into an adulterous relationship with Cindy Hensley. He became engaged to Cindy while still married to Carol.
Carol, having raised John McCain's children and endured so much more, was not even mentioned in passing the biographical video played at the Republican Convention.