You only need to look at the divorce rate or ask any married person and they'll tell you that it's not all sunshine and roses spending the rest of your life with the same person.
So it's almost a scientific fact that the ABC's new four-part factual series, Making Couples Happy, will appeal to many viewers.
In 2010, Aunty set about proving science could make individuals happy in just two months with the series Making Australia Happy.
From Thursday, four ordinary couples ranging in age from their 20s to 50s will embark on an eight-week journey to happiness and relationship fulfilment.
Laney and Darren, Alison and Paul, Carla and Domenic and Paula and Stephen will undergo group sessions, interventions and scientifically proven techniques to repair their relationships.
Every two weeks, they are evaluated and scored to determine their happiness levels by clinical psychologist and relationship specialist John Aiken, and sex therapist and relationship counsellor Desiree Spierings.
UK couple Paula and Stephen have been married for six years and together for eight. Paula is a full-time mum and Stephen is a project manager in Sydney.
They moved to Australia six years ago as a carefree young couple, but now have three kids under five and life was becoming an endless round of chores and arguments.
"We were just arguing all the time and it felt like we were stuck in this rut and we weren't having fun anymore or working as a team," Paula says over the noise of their three children during the witching hour - the dinner, bath and bedtime tussle any parent or child carer will know all too well.
Stephen adds: "I could see that we were having problems and that there was something to be done to make our lives a little bit happier because it was a pretty miserable place we were at and we were pretty much living argument to argument."
The pair applied for the show after Paula saw an advertisement looking for couples who were looking to "to improve happiness through science".
"So I applied and didn't really take much notice, then before we knew it they were sending us a questionnaire and then the producers were in our house," she says.
While Stephen was open to the idea, he wasn't too keen on having cameras privy to the inner workings of their relationship.
"I was very nervous throughout knowing that everything you say has the potential to go on to TV for hundreds of thousands of people to see," he explains.
"However, when you started taking it seriously, as in listening to their advice and doing the homework, very quickly you actually forgot about the cameras and concentrated on what was wrong and how you could fix these things."
For Paula and Stephen, having a parallel journey with the other couples on the show provided some unexpected respite.
"They're all quite different to us but all had similar issues, so I guess it kind of made it easier because we were all going through the same thing," Paula says.
"It was just like our own little support group within everything that was going on."
At the risk of providing spoilers, it would be negligent not to ask the million-dollar question - are they happier?
"Without a doubt it's definitely improved our relationship and I think it's improved our children's lives as well," Stephen says.
"It's not like we're perfect, we're not the perfect couple with the perfect life. There are still tough times, as there would be in any life, but it's just now having the knowledge to identify where behaviours are inappropriate and reactions to that."
_·Get the spark back - see today's Mind & Body liftout. _