When it comes to mixing business and pleasure, the general consensus is … don’t do it.

The awkward small talk by the water cooler and avoiding each other in the break room just isn’t worth it, but that hasn’t stopped many of us from dipping a toe into dangerous waters.

Whether you’re messing around with a colleague or boss, or even worse – going into business with a family member, having your worlds collide is often a one-way ticket to disaster.

This is advice Kelly Clarkson may well be kicking herself for not following.

The 38-year-old has filed for divorce from Brandon Blackstock, after nearly seven years of marriage.

The couple tied the knot in 2013 and also have a complicated business relationship as Blackstock is Clarkson’s manager.

The couple have two children, River Rose, 6, and Remington Alexander, 4. Photo: Getty

A source close to the pair said their working relationship and Clarkson’s desire for more children caused tension in the marriage.

“Kelly and Brandon work together non-stop and that became a contention in their relationship,” the source told Entertainment Tonight.

“Brandon is the (executive producer) of her show, as well as her manager.

“Kelly has always brought up wanting more children, which Brandon doesn’t.”

Fortunately for Clarkson, she’s not the only famous face who has had to navigate an awkward business/pleasure relationship.

Christina Aguilera and Jordan Bratman

“He’s got those lips like sugar cane” – that’s according to Xtina, anyway. Photo: Getty

He’s the sweet-talkin’, sugar-coated candyman that swept Aguilera off her feet in 2001.

Back then, Bratman was working at Aguilera’s manager’s company Azoff Music Management.

The two tied the knot in a lavish $3 million ceremony in 2005 and welcomed a son before Aguilera called it quits in 2010.

“It got to a point where our life at home was reminding me of my own childhood. I will not have my son grow up in a tension-filled home” she told People.

Macauley Culkin and his parents

Kit and Patricia Culkin were keen to get their hands on the Richie Rich star’s cash. Photo: Getty

Our parents are supposed to only want what’s best for us.

Unfortunately, that wasn’t the case for the Culkins, whose divorce turned into a bitter legal battle about who would get control of the young actor’s fortune.

Culkin petitioned to be emancipated and won control of his $US17 million fortune ($25 million) at just 16 years old.

“My father was overbearing. Very controlling. He was always the way he is, even before my success,” Culkin said in 2004.

“He’d play mind games to make sure I knew my place.”

Heidi Montag and Spencer Pratt

Bad romance: Despite their toxic history, the couple has remained together. Photo: Getty

This relationship stands out from the rest as an example of exactly what not to do when mixing business and pleasure.

The couple met and began dating when filming The Hills in 2007, with Pratt becoming Montag’s manager soon after.

In 2008, the couple was worth $US10 million ($14.7 million), but under Pratt’s management the pair had blown through their fortune within two years.

Montag fired Pratt (and hired a psychic as her new manager) and reportedly filed for divorce, after which Pratt shared his revenge-porn plans with US Weekly, stating he was “looking forward” to selling Montag’s sex tape.

Miraculously, they rekindled their romance, renewed their vows and now have a son together.

Robert Downey Jr and Susan Levin

Sometimes Hollywood romances really do have Hollywood endings. Photo: Getty 

Proving that, sometimes, love wins, is reformed bad boy Robert Downey Jr and the woman who helped save him.

RDJ met producer Susan Levin when he was in the midst of a highly publicised downward spiral in 2002.

The two met on the set of Gothika, after the actor had served a six-month jail sentence and had just completed a court-ordered stint in rehab for his addiction to heroin and cocaine.

“The old saying is true, behind every good man there’s an incredible woman,” RDJ told the Herald in 2010.

“I owe a huge amount – if not all – of my success to Susan. We make a great team.”