Here, how to make love last by reinventing ourselves – and our relationships as we age.

The actress Candice Bergen is a surprisingly good writer. And while I loved the dish about her fearless embrace of carbs in her memoir A Fine Romance, what really imprinted on me was her love story with her first husband, French film director Louis Malle.

They married at age 34 and 47, respectively. They sustained their love affair, separated by film sets and continents, with fervid epistolary exchanges. Here is Malle: “Let’s get together, my love, not for three days or a weekend, between planes but for time, experience quiet, isolation, silence together. And talk, about things, about the future. And let’s love each other, let me enjoy what I miss so much when I am away from you.”

In this letter, Malle, who died with Bergen by his side after 15 years of marriage, nails some of the key ingredients for keeping a passionate marriage alive. Their love story includes intrepid and glamorous travel adventures; it also includes Bergen worrying about losing Malle if she doesn’t fuss enough over his dinner. She shows us that you can’t really love someone if you don’t fear losing them, and they continually vow to try harder to make each other happy. Their story also proves the great power of spending quality time apart and the pull of a partner with an independent life.

Joan Price is the California-based author of The Ultimate Guide to Sex After 50: How to Maintain – or Regain! – a Spicy, Satisfying Sex Life. It’s a field guide to making love last by reinventing ourselves and our relationships as we age.

Price explains why separate adventures inject a relationship with zest: “If you’re never apart, how can you crave each other? If all your experiences happen together, how can you bring anything new to each other? A major libido killer can be too much time together, especially if you’re both retired and spending your days and nights together. To spark your libido, you need time apart and new experiences on your own.”

Other concepts Price identifies as relationship cement are mystery, surprise, adventure, novelty and affection. She suggests planning date nights, leaving each other sexy messages, unexpected gifts, nostalgic soundtracks and the writing of love letters as a way to strengthen connections. Price is also an advocate of spicing things up, with lingerie and accoutrements; she is practically an evangelist for the sex toy industry.

But in terms of a long-term relationship, in real life, things get stale.

Price’s answer is to just do it already. If the desire isn’t there, start making out anyway: “I can’t emphasize enough how important it is to approach our sexuality in this new way: relax, start getting physically aroused, emotional arousal will happen and, voila, we’ll be in the mood. Commit to regular sex, partnered or solo.” She suggests scheduling sex dates, paired with rituals that signal to your partner that sex would be welcome. “Make sex a habit. The more you do it, the more you’ll want to do it.”

But back to the wooing power of words, the ultimate aphrodisiac.

My favourite inspirational success story of a later-in-life romance is Must You Go? by the brilliant British historical biographer Antonia Fraser, who was married to the brilliant playwright Harold Pinter. The pair met in their early 40s, both married to others (Fraser with six children), and they remained together until Pinter’s death at 78. Fraser’s memoir is the actual diary entries of their relationship, published in 2010.

What stands out is the steadfastness of their love; the concern they show each other; and how they feed their romance with words. The pair are also letter writers, but Pinter ups the ante by making his odes public. His poem To Antonia includes these heart-stopping lines: “She dances in my life/Still you turn in my arms/Still we clasp/Still you swim in the big and brilliant bay/And come backing the wave/To my side.”

Well, of course, having Harold Pinter write a poem about you is the ultimate. Let’s just scale down expectations – for the rest of us mortals, a little romance goes a long way. Making everyday life exceptional is a much grander vision of a relationship, of a life shared. The element of yearning has to be nurtured in word, thought and deed.