"We went from being good friends, to just having a lot of the same friends, to being together for a while.
"And everything ended fairly amicably.
"It was just one of those phases I guess. You go through it and you learn a lot from it."
At the time of their break-up, Cyrus addressed the reports during a fiery Instagram Live.
"Two halves can't make a whole and we're individually just working on ourselves to become the people that we wanna be, like everybody else at this age," Cyrus said at the time.
"We've been friends for 10 years and we're going to continue to be friends, so just don't make it something that it is not."
Simpson had previously been in high-profile relationships including with supermodel Gigi Hadid, billionaire Kylie Jenner and actress Bella Thorne.
The star's parents, Angie and Brad Simpson, also appeared on the programme, where Stefanovic asked them what they thought of his famous girlfriends.
"He's had a few very high-profile relationships. Along the way you would've been supportive of all those girls like any mum?" Stefanovic asked Angie before bursting into laughter.
"Some I were … You're a bugger [Stefanovic]," Angie said.
"He had some lovely girls. We've had some interesting rides and dinners at people's places where you're just like … [mind explodes].
"He's a romantic. A hopeless romantic. When he falls, he falls hard."
It's understood Simpson has since moved on with Dutch model Marloes Stevens.