Above: Robert and Jane celebrating their Wedding, 1962
There comes a time when you are ready to settle down. I was 22 when I reached it - young by today's standards, but I'd had a great time, travelled, partied, made good friends. I just hadn't met The One until I danced with Rob at a friend's party. He was 26, good-looking, charming, witty, with a glamorous career in advertising. He could even cook - though, I later discovered, I was not the only girl to dine at his bachelor flat on devilled kidneys (his one recipe).
Anyway I fell for him and by some miracle he fell for me. It took us nearly a year to get engaged and we were married three months later, a church wedding with the reception in my parents' garden.
By the time I had gathered stories and advice from couples of all ages, and read comments on marriage by authors as diverse as Charles Dickens and Groucho Marx, I was amazed at how much all married couples have in common - from the things we row about (from mothers-in-law to back-seat driving) to the things we appreciate in our partners, such as the unexpected compliment.
The down side? Recurring arguments about money (the single biggest cause of split-ups).
One partner's necessity is the other's reckless extravagance. But for us, as for most couples, it's how you react to the trivia of everyday life, the petty irritations as well as the small pleasures, that determine whether a marriage is a success. In all marriages there are landmark times when marital harmony is particularly at risk.
Below, I have itemised four key 'danger zones', the rocks around which many a marital ship can founder.
DANGER ZONE 1: POST-HONEYMOON BLUES
Like most brides of my generation, I looked no further than the honeymoon. I never paused to consider what 'happily ever after' actually meant. Sooner or later, for all newly-weds, the romantic bubble bursts.
Being married is not the non-stop love fest you expected, and your partner seems to have morphed into a different person. It's not surprising if you wake in the night, thinking: 'Oh my God, have I made a hideous mistake?'
As she walks down the aisle, the last thing the bride is thinking about is having to retrieve her husband's towel from a pool of water on the bathroom floor on a daily basis.
Likewise, he isn't dreaming about cutting his chin with a blunt razor because she's just shaved her legs with it.
But, neither of them has made a hideous mistake. They are simply making the transition from the heightened, feverish emotions of being 'in love' to the long-term business of loving each other, warts and all.
To get over the shock of your partner's domestic habits, you need tolerance, along with an ability to see the funny side.
Give in gracefully about trivial things. Save your powder for the big issues.
Play to your strengths - if he's a brilliant cook, let him do it. If you are a whiz at DIY, put the shelves up.
Don't think you can 'marry the man today and change his ways tomorrow,' (as Adelaide sang in Guys And Dolls). Be warned, it doesn't work.
DANGER ZONE 2: BABY, IT'S HARD WORK
I became pregnant with Sophy eight months after we married, and Hugh arrived just 12 months later. The small age gap meant the nappy-changing, baby-food shoveling period was over relatively quickly but, nevertheless, I was a zombie mum for four years.
Even in the swinging Sixties, it was normal for wives to be stay-at-home-mums while their husbands went out to work. Today, mercifully, it's different, and most dads share childcare and chores.
Looking back, I can see that Rob was amazingly tolerant. Our marriage might never have survived if it hadn't been for family and friends.
First of all, my friend and neighbours got a group of mums together and organised a child-minding rota, so two afternoons a week were blissful free time. Second, my mother-in-law and my mother volunteered for childcare.
I'll never forget the first holiday without them. We stayed with friends in Greece, and sun, sea, good food, wine, adult conversation and sleep.
Most grandparents love to be used, so make friends with your mother-in-law. There's no need for husbands to feel excluded. Plan how to share childcare as well as household chores. Keep friendships in good repair. When you're stuck indoors with a couple of toddlers, a moan on the phone can stop you taking it out on your partner later.
DANGER ZONE 3: KEEPING THE FAITH
In answer to the question 'Should couples remain faithful to each other?' everyone I asked as research for my book - men and women - answered 'Yes'. I do, for now. The average British marriage lasts 24 years, with two in five ending in divorce They all felt their sex life was a precious part of their relationship, not to be shared with anyone else. 'If you're going to break your vows, what's the point in getting married?' said a friend.
But even in the happiest marriages, an urge for extramarital adventure occurs now and then. If you make it past the seven-year itch, it may hit again at 14 years and then after 21 years.
It's partly to do with wanting to prove you're still attractive, and partly boredom. The grass can look so much greener outside your marriage, especially in that meadow where your newly divorced friend is frolicking with her handsome, rich new lover.
Even if whole-hearted forgiveness is forthcoming, once trust is broken, it can take many years to restore it.
Be aware of the dangers and recognise the urge for what it is: a temporary itch, not to be scratched. If your partner strays, work through the problem together, with professional help if you feel you need it. If you know that a friend's husband or wife is cheating, never, ever tell them. It's none of your business.
DANGER ZONE 4: FRICTION OVER 50
Retirement can bring out hidden marital friction. After retirement, both partners are together day in, day out, seven days a week. Mannerisms formerly hardly noticed become unbearably irritating, and bickering replaces conversation. I have watched my grandparents and parents go through this. Most couples look forward to having time to do the things they never got around to. But it can turn out that, if one partner is happy and occupied, the other is at a loose end.
With this in mind, I dragged Rob to computer lessons. Now, though he is only semi-retired, he's glad he went. If you want to investigate your family's genealogy, check out Test cricket batting records or create a garden pond, the how-to is yours at the tap of a few keys.
If you miss the buzz of a work environment, return part-time to that world, perhaps in a voluntary job. If you always wanted to paint or learn Bridge, tap-dancing or yoga, do it now. Whatever new activity you choose, start it before inertia sets in.
Our path may have led Rob and I over rocky ground here and there, but we have reached the sunlit uplands. It is the laughter more than anything that has made it all worthwhile. Above all, we cherish our family, the product of our marriage and an essential part of it.
Above:Jane with her grandsons. "We cherish our family, the product of our marriage"
Isn't that a beautiful story? What have you done to keep your marriage strong?