Arnold Schwarzenegger: Success and secrets

Arnold Schwarzenegger rose to the top in bodybuilding, movies, and politics, and then lost his marriage to infidelity

He says politics had brought Maria - a Shriver and a Kennedy -- too many disappointments and tragedies.

Stahl: You had no idea that this was something she would not want to get back into?

Schwarzenegger: No. As a matter of fact, I was thinking that she would say, "Wow, that is amazing, welcome to the club. We finally convinced you to be a public servant, just like my entire family." None of that. So all of a sudden it came to a grinding halt and I had to now deal with the drama.

He says the race was off until his mother-in-law, Eunice Shriver, stepped in and told Maria, "If you stop him, he'll be angry for the rest of his life." And, so, Maria gave up her career as a TV news journalist, and jumped in with both feet.

[Maria Shriver, campaign speech: As a Democrat, I'm totally comfortable supporting him.]

She went out on the campaign trail and even defended him when he was accused of groping more than a dozen women from earlier in his career.

[Maria Shriver, campaign speech: You can listen to all the negativity and you can listen to people who have never met Arnold, or who met him for five seconds 30 years ago. Or you can listen to me.]

But by this time Arnold had already had the affair with the family housekeeper, Mildred Baena. And would later learn there was a son, Joseph. He says there were strains in his marriage while he was governor. The day after he left office in 2011, Maria wanted to talk.

Stahl: Maria wants to have a meeting with your marriage counselor. Tell us about that meeting.

Schwarzenegger: That particular visit that you're talking about was the visit where she then said, "Hey, I think that Joseph is your kid. And, am I off here on this or-- or not?" And I said, "You're absolutely correct." And I had to face up to that, which I have been kind of hiding but no one knew about. And that I knew about at that point maybe for five, six years or so.

Stahl: You just said, "You're absolutely right"?

Schwarzenegger: I said, "You're absolutely right, and I am sorry." It was very painful for her. She was very disappointed.

Stahl: Maria asked you, "Why didn't you tell me?" And what did you say?

Schwarzenegger: That I did not know how to.

Stahl: You didn't know how to tell her?

Schwarzenegger: How to tell her without worrying about, you know, that it would get out or whatever.

Stahl: And that she'd leave you while you were still governor.

Schwarzenegger: I don't think that was as much of an issue as just how do I keep this under wraps.

Stahl: Well, tell us how it happened. This is a woman who worked in your house--

Schwarzenegger: Exactly. And I found out about it kind of-- seven years in or eight years in--

Stahl: Well, wait, wait, wait. You-- wait. You have this relationship. Nine months later she's-- has a baby. Didn't you say, "Oh my God, it's my baby?"

Schwarzenegger: No.

Stahl: You - it never crossed your mind?

Schwarzenegger: No, because she was with a man and she-- so no.