The `Kiss from a Rose` hitmaker - who raises four children Leni, seven, Henry, six, Johan, four, and two-year-old Lou with the supermodel - believes a strong friendship is the key to a lasting relationship because respectful partnership can be built on it.
He said: "I look at my wife as my best friend, the mother of our children second and my wife and lover third; because as wonderful as love is, it can get curly pretty quickly. But when you respect your best friend there is a line which you rarely, if ever, cross."
While the 48-year-old musician is blissfully happy with his wife, he is pleased they didn`t meet until later in life as he doesn`t think he would have been mature enough to make their relationship work when he was younger.
He added to the new issue of Cosmopolitan magazine: "I think most men are useless before the age of 40. If I`d met my wife Heidi in my 30s, it probably wouldn`t have worked, due to my immaturity. I was 40 when we met - she was a fashion model and three weeks pregnant [by her ex-boyfriend Flavio Briatore] although she didn`t yet know, and I was a singer in a profession not known for people being responsible. But when we fell in love we saw something in each other that transcended everything else."