My parents did not expect me to land a place at university. I was not considered academic enough. And anyway, I was a girl. Instead, I was being primed for marriage. My mother didn’t see anything wrong with this. Born in Britain between the two world wars, when the scarcity of men had made them precious commodities, she had left school at 14, part of a generation often brought up to believe that matrimony was the only guarantee of a secure social and financial future. While romance and indeed love were a bonus, the unwritten clause in a marital contract stipulated that a wife must play her supportive part at home while the husband went out to work. Without the necessary qualifications for the role, the entire agreement risked failure.

In 1972, I was at college studying for my A-levels, but in the holidays my mother enlisted me on various “finishing” courses. Her intention was that I acquire the domestic skills to enhance my spousal eligibility, including how to cook, carve a roast and drive a Jeep to the shops, in case I landed a nice gentry farmer. Only now, almost 40 years after her death, do I realise how much she regretted the lack of educational and career opportunities open to her. Only now do I sympathise with her subconscious envy when they were offered to her daughter.

While I allowed my mother to manoeuvre me towards a well-cushioned altar, my own ideas of future independence were forming. Tentatively, I mentioned the university option to my mother. At first, she managed a tone of considered scepticism, before concluding with a firm “out of the question”. My divorced parents exchanged tense letters about my future. “Juliet is not university material,” my mother wrote. My father replied that it would be “spine-strengthening” for me to have a go, even if I failed. Despite my dismal exam record, my father had recognised his daughter’s incubating passion for reading, poetry, theatre and writing. So had my English teacher. At the time, I had no idea that Mrs Fitzgerald, with her falling-down half-bun, chewed red biros and battered brogues, secretly hoped to make enough money to leave the teaching profession and become a novelist. But her encouragement was inspirational. So, I sat the Oxbridge exam.

At around that time, I met James, a clever, arty, curly-headed charmer who was working for a travelling discotheque company as their star DJ until he found his professional calling. My mother was dismayed by my choice of boyfriend. My father said he looked like the young Byron. I was smitten.

James lived in a tiny mews flat in London above a stable, the musty, horsey scent permeating the sitting room in a way that I found as thrilling as when, on our first date, he played Here Comes the Sun at top volume on his tiny portable record player, and life began to glow.

One rainy December evening, I was on my way to a Christmas party when a damp brown envelope marked “Telegram” flopped through my letterbox. I read the pasted-on typewritten words at one glance: “Vacancy offered you to read English Literature, autumn 1973. St Hugh’s College Oxford.”

Shoving the telegram in my pocket, I went to the party and told no one. Not even James.

The next day, a second telegram arrived. The university would offer the place to the first person on the waiting list if they did not receive an acceptance from me by 27 December.

On Boxing Day, I rang my father and told him my news. He was momentarily silent until his delayed shock was so great that he dropped his favourite coffee cup and I heard it smash.

Then I told him I was turning the university offer down. I was going instead with my DJ boyfriend to Iran to work as his assistant in a disco in the Tehran Hilton. My father said nothing.

The next day, a letter arrived. My father, thrifty but not trusting the post and aware of the urgency, had hired at what must have been considerable expense a motorcycle messenger to bring a letter from his home in Kent to me at my mother’s house in Hampshire.

The letter consisted of two typewritten sheets marked A and B. Sheet A was headed “Why I should go to work in a discotheque in Tehran” and itemised the virtues and advantages of this option: a wonderfully rich culture to explore, financial rewards, lovely music, romance. There were not many points, but they were certainly plausible pluses.

Sheet B was headed “Why I should be the first woman in our family go to university” and argued the case with such fluency, persuasion and irresistible seduction that the decision was suddenly a no-brainer.

For my father’s next birthday, I presented him with the glued-together coffee cup. Apart from guiding me towards the immense privilege of going to university, his letter changed the way I approached big decisions thereafter, weighing up the pros and cons of life’s dilemmas with equal care. It also gave me a new confidence to just have a go, even if everyone (or almost everyone) tells you not to.

James never went to Tehran. He stayed behind in London and eventually I married him. In 1979, my English teacher’s novel, Offshore, won the Booker prize. I remain useless at cooking.