After a lovely 25th birthday trip to Vienna, I returned home to face the reality of my quarter-life circumstances. I had been happy with my milestones to date – a degree, a stint of modelling on the European and New York runways, a couple of relationships and some encouraging writing contracts – but was then told by my mother what my grandfather Alexander Chancellor had pulled off by the time he was my age.

Having moved to Italy to work for Reuters news agency, he spoke Italian fluently and had married my grandmother, Susanna Debenham; he had two children, he had bought a house and even had someone iron his shirts from time to time, which Susie was definitely not going to do. By the time he reached 35, he was editing this magazine.

My generation grew up watching their (our) parents’ marriages fail

Before the despair sank in, I reminded myself of the difference between Alexander’s twenties and my own. When he was my age in 1965, the economy wasn’t malnourished, university degrees were paid for by the state and conferred prestige and opportunity, while people sent and received flowers in person rather than on Hinge. Added to which, his generation were provided with a road map for life. All they had to do was follow a set of cut-and-dried social duties and the outcomes would on the whole be pretty agreeable.

One such duty was marriage. Even in the 1960s, when everything was up for grabs, marriage remained an institution conferring stability. My grandparents remained together for 55 years until Alexander’s death in 2017 – a bond virtually unheard of among the divorce-prone Gen X. Their secret? They weren’t in love – or rather, they weren’t romantically in love, not at first anyway.

Susanna had been working as a secretary. Having no real plans for her future, she consulted a respected elder whose advice was to find herself a husband: ‘I mean, what on earth else will you do?’ Shortly afterwards she happened upon my grandfather. ‘He’ll do nicely,’ she thought to herself. ‘He ticks the right boxes.’ Their families were linked already, because Alexander’s aunt Angela Paget had married Susanna’s uncle Sir Piers Debenham, and that turned out all right.

There were no sweeping gestures, no spontaneous trips to Paris and no grand declarations. As plain as it may sound, they simply got on well and maintained a mutual fondness.

I am told that their decision to marry came as a solution to the problem of who would replace an empty milk bottle. A milk bottle might seem a mundane catalyst for marriage, but marriage is built on mundanities. Neither demanded that their partner be a 24/7 shrink, a psycho-spiritual portable battery or a sexual and romantic muse. Neither expected the other to be faithful. They were simply maintaining a tried and tested institution, with the cultivation of tenderness as an added benefit.

Gen X – my mother’s generation – has a very different idea of what marriage ought to be. Born during the buzz of 1965-1985, they came of age in a psychedelic and sexual revolution fuelled by the advent of birth control, no-fault divorce laws and rising individualism. Their romantic optimism was reflected in songs like ‘Let’s Get It On’ and ‘All You Need is Love’, and movies like Grease and Manhattan.

But this tomfoolery took its toll: marriage rates began to decline sharply, with each subsequent generation following suit in an apparent race to the bottom. The Silent Generation – born, like my grandparents, between 1928 and 1945 – had marriage rates of 81 per cent. Gen X was only 53 per cent, millennials (born between 1981 and 1996) only 44 per cent and Gen Zedders like me (born between 1997 and 2012) are projected to have the lowest marriage rates yet. I’m no statistician, but I suspect these aren’t your normal ebbs and flows.

The downstream effect of Gen X’s hedonistic approach to romance is that my generation grew up watching their (our) parents’ marriages fail. Marriages built on romantic love alone, they discovered, could not last. This resulted in a divorce rate spike and Gen Z’s subsequent scepticism about marriage altogether. The problem is that we have been inculcated with the same romantic ideals as our parents: 81 per cent of my generation value marriage, despite having the lowest projected marriage rates on record.

This has led to love being more safely entertained in the mind than in reality – marriage- and relationship-themed reality TV shows like Love Island, The Ultimatum: Marry or Move On and Age of Attraction are more popular among Gen Z than any prior generation. Dating apps have also become a form of entertainment for us: it’s all fun and games swiping to discover who finds you attractive until someone ruins the mood by trying to initiate an actual date. A minuscule number of dating app matches lead to a relationship. In fact the only instances of success I’ve come across have been when both parties already knew each other in person before matching.

All of which is to say that Gen Z’s lack of matrimonial success stems from an inner conflict. In losing faith in our parents’ model of marriage, we’ve also begun to lose sight of an older one – marriage as a practical partnership from which love evolves, rather than a romantic ideal on which it entirely depends. And only the former has ever lasted a lifetime.