In 1964, the year after the Annus Mirabilis when “sexual intercourse began”, according to Philip Larkin's poem of that name, I went to boarding school in England, a convent in the south of the country. I was 12.

Over the next five years that I was to spend at this school, I became close friends with two girls. One is of particular relevance here.

She was a few months older than me, an orphan who lived with her older brother, two older sisters and their old nanny. And she had a boyfriend who was 21 and who had been her eldest sister's boyfriend before.

The man who, in retrospect, seems distinctly creepy, seduced (as in, had sex with) my friend when she was 13 or 14. She was a tall, beautiful girl and she was what used be called “well-developed”. So you could say she didn't look much like a little girl. Never mind ditching the older sister for the younger one, never mind taking advantage of her newly orphaned status (I myself also had a terrific crush on this man).

I remember thinking there was something not quite right about the situation. He and a couple of his friends would come to visit the school and take us out for ostensibly artistic jaunts (to visit the grave of the composer Delius, for example).

Once the arty bit of the outing was over, we would find a nice field, drink some wine and roll around with these guys. They would be tickling us, feeling us up a bit, maybe even snatching the odd kiss. All quite harmless. Or was it?

Had we been adults, I don't think we would have given these men a second look. They weren't Adonises. And had we not been convent schoolgirls, I don't know that it would have seemed such fun for them either. It was fashionable then, not just to admire Nabokov's Lolita (which had only been published in Great Britain less than 10 years previously) as a work of art but also to embrace it wholeheartedly, to regard it as exemplary. So we were the Lolitas and they were the Humbert Humberts.

Fast forward to the early 1970s. We were all crazy by then, in a kind of ­desperate, anxious, needy way. The drink, the drugs, the sex, the rock' n' roll, they were all beginning to take their toll. I wasn't made for the fast life but I was living it nonetheless. There didn't seem to be any choice. The hippy period is always presented as gentle and flower- childy but it wasn't like that. It was too frenetic.

The recent revelations by Mackenzie Phillips that she had an incestuous relationship with her father, Mamas and Papas singer John Phillips, aren't really so surprising given the hothouse climate of sexual mores then. It does, however, remind one, if indeed one needed reminding, that the hippy era was not without casualties. She may forgive her father. I'm not sure that I would. Of course, he was out of his mind on drugs for most of the 10 years, but she was still his daughter.

At least she was semi-grown-up, not a young child, but he was 44, more than 20 years her senior. John Phillips is dead so we can't ask him what he thought he was doing. The fact that their first encounter took place the night before she was due to marry Jeff Sessler, a member of the Rolling Stones entourage, ­suggested that Daddy was determined that he would have his little girl before Jeff did, though history — or rather the ­news­paper cuttings — doesn't relate whether Jeff had already slept with his bride-to-be.

By 1975, I was living in London after a turbulent and promiscuous spell at Edinburgh University, followed by an equally rackety period living in Oxford and working as a waitress. I was 23 and my parents had bought me a flat near Ladbroke Grove. I had a sort of job (which I was soon to lose) and I had a boyfriend. He was a tall, rangy Australian called Andrew Fisher, 17 years older than me.

Sadly he is now dead, having ­succumbed in 2008 to galloping ­Alzheimer's. Andrew once told me that his mother said: “Women will lie down in gutters for you.” I don't know whether any ever did, but the list of his sexual conquests was very long. Andrew had been part of that quintessential Sixties and Seventies group that included Richard Neville, Felix Dennis and Germaine Greer. This was in the days of Oz, the underground magazine that once published a spread of Greer's vagina and subsequently got into legal trouble under Britain's obscenity laws for publishing a highly sexualised Rupert Bear parody.

As founder and editor of Oz, Neville was the linchpin of the underground press and could be said to have shaped the hearts and minds of at least two generations — his own and the one that came after it. A large part of the responsibility for all the tuning in, dropping out, freaking out, chilling out, hanging out, getting high, giving up, giving it away and cooling it, man, that went on, can be laid at Neville's door. As the poet Hugo Williams put it: “Post-1966 was all long hair and psychedelia.”

They were older than me, by some 15 or more years, and Oz had ceased publication by the time I met Andrew while I was working briefly as a nanny in the boiling summer of 1976 for ­Richard's sister, the novelist Jill Neville, and her then husband, journalist David Leitch (both now also dead). But its spirit lived on.

Jill and David maintained what could be described politely as a bohemian household, the former perhaps more than the latter. Jill, a beautiful, tricky, manipulative woman, had many admirers. David was fighting a losing battle with alcoholism, but the atmosphere in their Little Venice house was infused with a kind of dangerous fun. You could always be sure of meeting interesting people — it was there that I first met Christopher Hitchens and Jeffrey ­Bernard (Jill was having a fling with the latter, but he took a liking to me and offered to make me the fourth — or was it fifth — Mrs Bernard; Jill was not pleased).

More than for any pleasure that it might bring him, Andrew, I think, really believed in sexual freedom as a way of life or a philosophy. I don't believe he was the only one. After all, Neville in his memoir of the period, Hippie ­Hippie Shake, quotes Greer as saying, “The group fuck is the highest ritual expression of our faith — but it must happen as a special sort of grace.”

Andrew used to attend orgies, or group-sex parties, in a house in Notting Hill Gate, owned by a painter and his actress wife and was very keen that I should go with him. I would never agree to go, though I once went and spent the afternoon in bed with a friend of his, an actor who lived in a flat in Mayfair. I can't remember why I did this: curiosity, daredevilry, a desire to please or impress Andrew. I didn't enjoy the experience and I hated the actor, whom I blamed for the whole sordid business, rather than Andrew. In the obituary that Neville wrote of Andrew for the Sydney Morning Herald, he said: “Even amid the sexual extroversion of the 1970s he pushed the boundaries with his staging of intimate erotic scenarios in London and Paris.” Perhaps he was thinking of these parties.

Andrew was never pushy or predatory — he didn't need to be: women were queuing up, if not actually lying down in gutters — but many men were. The advent of the so-called sexual revolution permitted predatory men to force themselves on girls too ­inexperienced, shy, nervous, or even too ambitious to say “No”.

More than once (or even twice), I ended up in bed with men who had bullied and bored (a lethally effective combination) me there. I still shudder to remember a night with a well-known art dealer who wouldn't take “No” for an answer and complained when I wouldn't give him a blow job.

He snored so loudly that I went to sleep in the other bedroom. I sometimes think he might be the reason I left London — to avoid bumping into him. Or a man who went on and on till I gave in, then said “You see, you wanted to all along.” No, no, I didn't, but, having agreed, I thought I might as well try to enjoy it.

The fear of being labelled a prick-teaser played its part too. The contraceptive pill undoubtedly made some things easier and, in some ways, better. But it also made many things more difficult. Free love was never free — you just paid in different ways. I don't think any of my female contemporaries would consider that they had been happy then, when we were supposedly young and free. There was something rather frightening about this freedom — it meant freedom not to call (I lost my virginity when I was 17 to a boy whom I was mad about, and he never telephoned me again; it took me years to recover); freedom to be unfaithful; freedom to steal your friend's boyfriend (which I am ashamed to say I did in my gap year).

Men definitely got a better deal from free love. Whatever women said and did, they were always more vulnerable. At least when women could say, “We can't. I might get pregnant”, it was a reasonable excuse. With the advent of the Pill, all that went out of the window. There were no more restraints.

In the past teenagers had always tended to be replicas of their parents. That all changed to produce a hugely confident and conceited generation. The next crop was total anarchy. Suddenly you were 17 or 18 and, for the first time, you could decide what to wear, how to do your hair, when to get up, when to sleep, whatever. There was no one supervising you. If you had money and looks, you had everything. And you could sleep with who you wanted.

Except you couldn't. There was just as much anguish and unrequited love around then as there always was. And sex only made it worse.