"When you leave a relationship there has to be some f***ing crazy story or some crazy drama. And the f***ing ghosting thing, like literally, I still don't even know what it is. It's just its own beast. We were in a relationship and then it didn't work any more.
"And we both decided to separate. That's it," she said.
Theron has two adopted kids, son Jackson, four, and baby daughter August, and when the pair realised the romance may not be progressing as it should they mutually decided to end things so as not to disrupt the actress' family.
"We were very, very new in a relationship. There was an understanding that I was a single mum with a very young boy who I had to put in a situation where he understood that mummy dates but that he does not have a father, you know what I mean? You have to be very careful and very honest about that stuff. And Sean was great with all of that ... The stories that Sean was going to adopt Jackson, and all of that was not true. It's not something that happens in 18 months. You can't do that to a child."
Theron adopted August in July 2015 at around the same time the engagement was broken off and she knew it was the correct thing to do as 55-year-old Penn - who has two grown-up kids, Dylan Penn and Hopper Penn, with his ex-wife Robin Wright - wasn't interested in becoming a parent again.
She explained: "In my honesty about wanting to have more kids, there was an understanding that a relationship had to go somewhere before it was going to be what you hope for, which ultimately did not happen. I couldn't foresee that, but that stuff takes time and I think it's my responsibility as a mother to protect my child from that. And we had a very clear understanding. He knew that I was thinking about filing for another adoption, but that we weren't filing together."
Theron and Penn were good friends before they became romantically involved with one another and they are still in touch now as their separation was on amicable terms, she says.
- Bang! Showbiz
