We’ve always wanted to be that couple who giggle photogenically together in the surf. But take away the veneer of Hollywood gloss, and that kind of relationship just doesn’t exist.

Off-screen, the bonds we share with our loved ones are complex and messy. Sometimes we go crazy for them, sometimes they drive us crazy. And amid all the bumps on the road – the bickering over putting the bins out, or who’s jealous of who – there’s one conspicuous boulder.

Psychologist Dr. Liz Powell says an inability to be true to yourself is the biggest challenge that couples in long-term relationships face.

Writing for PsyhCentral.com, Dr. Powell says complete authenticity is the mainstay of any successful relationship. And it’s harder than it seems to achieve.

Take Sandy and Danny from Grease (above). Their relationship hit a rough patch because she was a bit too wholesome for him and his gang of boy-racing T-Birds.

Those two would have never lasted the distance in real life, since Sandy essentially had to change who she was - her bang-wearing, cardigan-toting, uptight soul – to fit in with Danny and the Rydell High crew. 

And we all know such a compromise can’t have had a happy ending. 

Read more: The bad relationship habits that jeopardise romance and kill long-term love

Dr. Powell also learned the hard way that being true to oneself is the only way forward when it comes to romance.

“I was in a relationship for four years that was great on paper,” ” she says. “By being in that particular relationship, I was doing exactly what everyone told me I should be doing. I got married. I did the monogamy thing.

“It was what everyone else I knew thought that I should do, but what I was really doing was making myself miserable.”

Eventually, Dr. Powell worked up the courage to forge her own path, but it wasn’t easy.

“Now that I’m being authentic and happy and joyful — yeah, there are some people who don’t like me as much,” she says. “I don’t necessarily fit in with them the same way I used to. But at least I’m being true to myself. I’m doing what I know I need to do for me.”

“ Always be authentic in all aspects of your life, and especially in your romantic relationships,” she adds.

“I was trying to be someone else in order to make other people happy and I learned that you can’t do that. You can’t be anyone but who you are. You have to be yourself.

“Do what it is that you want to do. Find that space to be fearlessly yourself and live from there.”

Images: Rex/Embodied Arts Collective