The singer said that it was getting a little uncomfortable discussing about their marriage in interviews given that they were no longer a couple.
"We're great friends, we love each other so much, and it just got to the point where it was getting a little weird," she continued. "There's no perfect time, so we just decided to do it."
"You can ask him, but it was just getting a little weird to laugh through the first date questions," she said, laughing.
"We just wanted to get adjusted in private. [And Axl's school has helped as] we have a co-op so Josh and I would walk there several times before the school season. I get to learn from the teachers and see how he reacts in a group of friends that he knows. And I get to help out and serve them snacks and clean the dishes. We have fun, we get down and dirty and read the stories with our costumes. You get down in the sand and get dirty - I love it. I love that part of it all."
The 42-year old singer and Duhamel announced last week that they had separated "earlier this year" after eight years of marriage.
"With absolute love and respect we decided to separate as a couple earlier this year," the duo said in a joint statement. "To give our family the best opportunity to adjust, we wanted to keep this a private matter before sharing it with the public. We are and will always be united in our support of each other and our family."
The singer and the 'Transformers' star married in January 2009 after meeting in 2004.