Schwarzenegger and Nielsen co-starred in the 1985 film Red Sonja. Nielsen wrote in a memoir published last year that she and Schwarzenegger had an "outrageous affair" while making the movie and that she didn't know until later that he was involved with Shriver.
In Total Recall, Schwarzenegger writes that he knew the fling with Nielsen wouldn't last and in fact it only made him realize that he wanted to marry Shriver.
The book is part of an effort by the onetime "Mr. Universe" and Hollywood action star to rebrand himself after leaving office with a mixed record and subsequent embarrassing revelations about a fling he had with the family's housekeeper. Schwarzenegger, who fathered a son with the housekeeper, says he also let the boy down.
Schwarzenegger, 65, said he avoided telling his wife for years about the boy, who is now a teenager, even when Shriver asked him, partly because of his longtime penchant for secrecy, and his fear that the news would become public and undermine his political career. He told his wife in January 2011, when she confronted him the day after he left office.
In an interview with 60 Minutes scheduled to air Sunday, Schwarzenegger said having sex with his housekeeper was "the stupidest thing" he ever did to his now-estranged wife and caused great pain to her and their four children. CBS aired excerpts of the interview Friday.
"I think it was the stupidest thing I've done in the whole relationship. It was terrible. I inflicted tremendous pain on Maria and unbelievable pain on the kids," Schwarzenegger tells 60 Minutes.
Schwarzenegger says he also let down the son he fathered with the housekeeper.
Shriver filed for divorce in July.
In his book, the usually ebullient Schwarzenegger admits to some loneliness, even though he packed his schedule with speeches, projects and movie-making after Shriver and the children moved out of the house. He said his career had been fun for 30 years because he shared it with Maria.
They had done everything together, he writes.
The former GOP governor also writes about a 2003 White House meeting with Karl Rove in which the top GOP strategist told him the recall would not happen and instead introduced the actor to then-national security adviser Condoleezza Rice as his pick to run for California governor in 2006.
Schwarzenegger felt snubbed.
He asks, "How could Rove have been so wrong?"
Rove's office said he was traveling Friday and could not be reached for comment.
Rice's chief of staff at Stanford University, Georgia Godfrey, said Rice cannot recall "any conversation on this subject."
"She has stated many times in the past that she has no desire to run for public office and those sentiments have still not changed," Godfrey said in a statement emailed to the Associated Press.
