Although it has been three years since Pete Wentz and Ashlee Simpson called it a day on their marriage, the Fallout Boy bassist can still remember how and why the breakdown of their relationship occurred.

Pete Wentz
Wentz recently opened up about his messy split from Ashlee Simpson

During a recent interview on Howard Stern's radio show, Wentz spoke candidly about an array of personal topics, including his and Simpson's tumultuous separation, the state of their relationship today and co-parenting their 6-year-old son Bronx.

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Wentz claimed his marriage began to fall apart in 2010 when his band took a lengthy break. "At 31, we'd had all these great years as a band, and then we took time off, and I basically became Mr. Mom," he said. "I had the beard, the flannel shirt. I didn't know what my identity was. That factored in. When your identity is what you do, it's hard when you stop doing it."

"It was the first time where I was like, 'Well, no one's really taking my picture. I'm just basically hanging out with my kid all day. Who cares?' I think when you stop caring about your personal appearance, your personal hygiene, it makes you even more depressed, but it makes you do it more," he continued. "It's like a vicious cycle."

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As well as his own issues, Wentz also thinks marrying at an early age was a big factor in their split. He tied the knot with Simpson in May 2008 at 29 and 24, respectively. "I think there's an important thing where you know how to fight, because you can fight with somebody and it's not the end of everything," he told Stern. "But if you don't know how to have those arguments, then they become nuclear. And we were doing this all in the public eye, which doesn't help."

Pete Wentz
Wentz with his girlfriend Meagan and son Bronx

Although Wentz thought their marriage was going to last "forever," he isn't resentful towards Simpson at all - but at the time the 35-year-old musician was angry with how they separated. "I would be an idiot to think that I didn't contribute to the unraveling of it. Of course, at first, I'm like, 'This sucks! You bailed on me!'" he said. "But you get perspective. We have a kid together. Our kid is awesome. He's great."

The duo have both moved on as Wentz welcomed his second son in August 2014 with girlfriend Meagan Camper, and Simpson had tied the knot with Diana Ross' son Evan Ross, 26. The pair are also expecting a baby.