Without a doubt one of the biggest showbiz stories of the week is the unexpected breakup of Heidi Klum and Seal. The pair — a poster couple for a successful interracial marriage — was thought to have one of the strongest relationships in Hollywood and all signs indicated they were in a happy, cohesive and loving union.

Their split after seven years of marriage has taken everyone, even ardent celebrity watchers, by surprise. Many would have gambled away their hard-earned cash on the power couple staying together for forever.

Every year the duo renewed their marriage vows; during interviews they would gush about how much they loved each other and were frequently photographed being extremely affectionate.

“I think people are shocked because they’ve always appeared to be such a close, family orientated couple,” said Donna McConnell, Showbusiness Editor of Mail Online.

“They made a big deal of renewing their vows in a wacky ceremony each year, and seemed to spend a lot of time together. So they just seemed rock solid, and with such a large brood of lovely children, they just weren’t one of the Hollywood marriages you predicted to fail,” says McConnell.

Unlike the majority of celeb pairings, it was rare, even unofficially forbidden, for the tabloid press to speculate about the state of their marriage.

“People really wanted to see this marriage work because it was an interracial couple: a symbol of what a post-racial society should be, people falling madly in love regardless of race,” says New York psychologist Dr. Jeff Gardere.

The couple presented an image of marital bliss, at least in the public domain, and was infamous for their elaborate Halloween parties and wacky customs which seemed to epitomize their perfect, easy-going relationship.

It is perhaps, though, the story behind how they met which fooled everyone into believing their marriage was immune to adversity.

Singer-songwriter Seal, 48, met German-born supermodel-turned-TV presenter, Klum, 38, in 2004 while she was still pregnant with her daughter Leni from a failed relationship with Italian businessman Flavio Briatore.

These forlorn circumstances did not get in the way of their romance and they married a year later on the beach in Mexico. To many it was moving that the soul singer proclaimed his love for Heidi during a difficult time.

Seal immediately assumed the role of Leni’s father. In 2009 he officially adopted Heidi’s child, and her last name was changed to Samuel. The couple went onto have three biological children together — Henry, Johan and Lou — and always talked openly about their devotion to each other and their multicultural “rainbow tribe.”

Perhaps for all these reasons everyone was caught completely off guard. We never expected Heidi and Seal to join the long list of recent high-profile celebrity breakups, including the likes of Kobe Bryant and wife Vanessa, Jennifer Lopez and Marc Anthony, and Deion Sanders and his estranged wife Pilar.

Even Will and Jada Pinkett Smith are constantly in the media amid swirling rumors of their pending split — but their end would not be totally unexpected.

Heidi and Seal’s separate careers have been cited as the factor in their separation. According to Dr. Gardere, “celebrity marriages often don’t work because they don’t spend enough time together,” he said, “travelling apart, working apart for days, weeks and even months at a time.”

Gardere also says celebs have too many distractions and unlimited options and this is not helped by the public adoration. “They can do anything they want to and divorce becomes more of a disposable item,” he says.

Despite all this, press and fans are in full-blown shock and there’s even chatter that the split is a publicity stunt to generate media coverage around the release of Seal’s latest album, Soul 2.

However, it could just be that Heidi and Seal’s spilt is a lesson for us all. There is no such thing as a “perfect marriage” and “real marriages” have trials and tribulations, and peaks and troughs. A successful marriage is about whether couples have the staying power to ride the storm.

Follow Kunbi Tinuoye on Twitter at @Kunbiti