My biggest failure as a father and husband:Arnold Schwarzenegger

Arnold Schwarzenegger opened up to Howard Stern Wednesday, admitting that his split from his wife of more than 25 years, Maria Shriver, was one of the biggest failures in his life

.

Stern first mentioned that the action star hadn't really had big personal setbacks in his life prior to the 2011 separation.

"I had personal setbacks, but this was, without any doubt, the biggest setback and the biggest failure. Without any doubt," he said. "Not only failure, but you feel like, 'I'm to blame for it. It was me that screwed up.'

"And you can't point the finger at anyone else. So yeah, I was disappointed in it. But it's always easy to be smart in hindsight. The thing was how do you make the best of that situation

The "Terminator" star was referring to fathering a child with the family housekeeper, which he admitted in 2011. That child is now in his teens.

Schwarzenegger, 67, added that after the two began divorcing, he sought "personal help," as Stern called it.

"Yes, we did, Maria and I, and it was the biggest mistake I've ever made," he answered. "That guy was so full of s***. I have to tell you. He said more crap and more nonsense ... It was just nonsense. Maria talked me into it. I went, and I felt instinctively maybe I shouldn't go because I know I screwed up. I don't have to go through anyone to have to explain to me anything, you know? I apologized to Maria. I apologized to the kids. Then, I tried to move forward."

But the actor and former governor of California said in the end, everything worked out so well: he maintains a friendship with his ex and is a respected father to their four children. He added he thinks people should get help when they need it, but it just didn't work for him in this situation.

Stern, 61, who went through a divorce himself in 2001, said the hardest part of the split is the kids.

"Yeah, but I tell you, my kids are a straight 10," he said. "I am so proud of them and I'm so in love with them."

He regaled Stern on his latest world premiere for "Terminator Genisys" and how his kids surprised their dad.

"I walk into the room and I see the room full of balloons. I check out who it is. I thought it was for the premiere or some congratulation notice. It was from all four kids and from my wife," he said. "There was a note — 'You're the greatest dad, the greatest man, you're the greatest this, you're the greatest that, we love you Dad' ... That's exactly the relationship we have."

He said this kind of love, even after a failed marriage, only happens if the whole family "works together."

"My wife was helpful, the kids were helpful," he said. "People around us were helpful ... I'm one of the fortunate ones."

The bodybuilding icon also opened up about his child he had that caused the marriage to end.

"He's terrific and he totally understands the situation. So, it all has worked out really well. It's a very tough situation for him. It's a very tough situation for my kids. Very tough situation for my family. It was tough for everybody," he said.