They leave the partnership with respect for one and other, wishing each other success and happiness for the future.
"We instantly clicked and talked non-stop for eight hours the night we met and I proposed after eight months.
Within three weeks she moved to Australia to be with me.
"Leaving and going to Australia, where Westlife hadn't been successful, gave me a chance to breathe, take a step back from my world and look at it from the outside.
I could just walk about unrecognised and start from scratch, and you don't have that media scrutiny that you have here," he says. One minute, I was a naive teenager serving burgers in Mc Donald's and two days later, I was in a music studio and signing a record deal.
Although it was a whirlwind romance, it was just so right from the beginning, so we knew it would work." There was no such certainty when 10 years ago he left Westlife, originally signed by Simon Cowell and managed by Louis Walsh, on the eve of its fourth world tour and emigrated to Australia.
"I wanted to launch my solo career, but it was more than that," says Mc Fadden, who, while there for eight years, was highly successful releasing his own albums, writing for a portfolio of leading artists, and being a judge on Australia's Got Talent.
She tells Australia's Vogue magazine, "There is so much I'd like to say.
I was really unhappy and I didn't know how to get out. I got there in the end." At the time of the split, the couple insisted the decision was mutual but Mc Fadden expressed his sadness via a post on his page, writing, "I love Delta and always will. I thank her for giving me the best years of my life.
"But I was young and, of course, I made mistakes - who doesn't in their teens and twenties?