"Marilyn was the Great Dimaggio's only love, the one who reached deep into his soul, where he kept his emotions under double lock," Morris Engelberg, Dimaggio's lawyer and friend in the later years of his life, writes in Dimaggio, Setting the Record Straight.
"For the last 37 years of his life, he ached at the thought of how close they had come to remarrying, only to be thwarted by her death."
Dimaggio's storybook 1954 marriage with Monroe fell apart after only nine months. Monroe went on to marry playwright Arthur Miller and died of a drug overdose eight years later.
"He wanted me to be the beautiful ex-actress, just like he was the great former baseball player," Monroe, 12 years younger than DiMaggio, once said.
The two apparently reconciled late in her life.
"The date of their second marriage was set: August 8, 1962," Engelberg writes. "But the kiss he gave her that day was far different from the one he had hoped for."
"That was the date Marilyn Monroe was buried. Joe leaned over her casket, sobbed that he loved her, and kissed her cold forehead," he writes.
DiMaggio, who died in 1999 at age 84, never spoke of her in public for the rest of his life, but his dying words showed his enduring passion.
"Joe Dimaggio was in love with Marilyn Monroe until the moment he died," Engelberg says. "He took his last breath fully expecting to meet her in that other world, which he was certain existed. 'I'll finally get to see Marilyn', were his last words."
The lawyer, who met DiMaggio in 1983, became his closest confidant in his final 16 years.
The book's publisher made the advance excerpts from the book, which is to be published early next year, available during the Frankfurt Book Fair, the premiere showcase for the publishing industry with editors from 110 countries.
Dubbed Joltin' Joe and The Yankee Clipper, Dimaggio still holds one of baseball's most revered records - a 56-game hitting streak in 1941. He was a three-time American League Most Valuable Player and a lifetime .325 hitter.
The book also tells of Dimaggio's hatred for singer Frank Sinatra and for the entire Kennedy clan because of the relationship President John Kennedy and his brother Robert had with Monroe.
"In the 1990s, Dimaggio was invited to appear at a charity event at the Kennedy Centre in Washington, and agreed to go only after being assured that no Kennedy would be there," Engelberg says in the book co-authored by Marv Schneider.
"When I asked why he would bar family members who had never harmed him, he responded: 'It's in their blood, and what they did to me will never be forgotten'," the book says. "They murdered the one person I loved."