The Candidly Nicole star, 40, attended her former best friend's November 11, wedding to entrepreneur Carter Reum in Bel-Air. The Simple Life co-stars were attached at the hip for many years but had a falling out in 2005 that derailed their friendship.
The House of Harlow founder and the DJ starred on the hit reality series from 2003 until 2007 despite their rift while the show was still in production. The Fox series (that eventually moved to E! for it's two final seasons) centered around Richie and Hilton as they were plucked from their luxury lifestyles and sent to rural areas to do blue-collared jobs.
“It’s no big secret that Nicole and I are no longer friends,” Hilton said in a statement at the time. “Nicole knows what she did, and that’s all I’m ever going to say about it.”
"And I think one of my favorite things about The Simple Life and one of my favorite things about doing it was, it really took us out of our everyday lives and put us in somebody else's world so I was always able to maintain a level of privacy and able to have my own life," the actress explained.
On the idea of a possible spin-off Richie said, "I think it would be hard now because we're older and we have traveled and we have been everywhere."