They've been married for 78 years, but he's never said 'I love you'. He explains why.

Morrie, 103, and Betty Markoff, 100, have been together for nearly eight decades.

In an age where almost half of all marriages will end in divorce, the Markoff’s know that their type of love is rare.

“We’re very lucky,” Morrie recently told Paul Laity of The Guardian from their Los Angeles home.

The 100-year-old couple – still married, still going strong. I wrote about the Markoffs, wonderful people https://t.co/af3negLPEJ

— paul laity (@paullaity) February 11, 2017

And while Morrie said there’s no ‘secret’ to his long-standing relationship – “the best I can wish you is our luck”, he said – there’s one peculiar thing about their marriage.

In their 78 years together, Morrie has not once uttered the phrase ‘I love you’ to his wife Betty.

Morrie prefers to use the word "care", as he believes "love is possessive".

"It's controlling and demanding. The word that I would rather use instead is 'caring'," he said.

"You care about people. 'Care', to me, has a much deeper meaning.

"Love [is a word] people also use to mean all sorts of off-hand things. 'I love playing tennis', and such. I hug Betty constantly, I kiss her constantly, I care very much about her."

MMOL discuss the dilemma of being single and lonely and not wanting to admit it.

Clearly, the pair also have a devilish sense of humour that has carried them through their 100 plus years in the world.

When speaking to Laity, the coupled joked their sex life was "just a memory".

"We’ve been together for nearly eight decades, and we still haven’t killed each other!" Morrie joked, while Betty aded, "we’ve tried a few times!"

Betty said couples should be aware of not letting "every complaint turn to anger".

"Tolerance and respect. And you've got to like them," she said.

With a love that is older than many people's grandparents, Morrie has no regrets with how he's lived his life with Betty.

"After 78 years, I can say I didn’t make a mistake. We’ve had our ups and downs, but we’re still here," he said.