During his speech, which was filmed in April but aired on June 17, Urban spoke about their first meeting, saying, "I felt a bit like I was meeting a real-life princess."

Urban spoke about his time spent in rehab shortly after their wedding, saying, "We got married in June 2006, and barely four months into our marriage, the addictions that I had done really nothing about blew our marriage to smithereens."

"I went into the Betty Ford Center for three months," Urban continued.

"Four months into a marriage, and I'm in rehab for three months with no idea what was going to happen to us."

"If you want to see what love in action really looks like, give that a whirl," he said. "Nic pushed through every negative voice — I'm sure even some of her own — and she chose love. And here we are tonight 18 years later."

Urban went on to say his wife has "the capacity to love like no one I've ever met".

The couple's teen daughters,  Sunday Rose and Faith Margaret, also made their red carpet debut at the event.

Nicole is the first Australian to win the AFI lifetime achievement award, and was honoured by a number of colleagues and friends, including Meryl Streep, Zac Efron and Reese Witherspoon.