Interesting track record: Bunkie King today; she first met Jack Thompson when he was playing a record in her mother’s lounge room. Credit:Nic Walker Mother is busy entertaining her guests and shows little interest in her adolescent daughter dancing in white sailor pants and a T-shirt late at night. Not that I expect to be noticed. While I have four strikingly attractive older sisters, I am a flat-chested, scrawny teenager. I have never had a boyfriend, never made out or even kissed. Several weeks later, on a balmy winter's afternoon in July, I am enjoying the school holidays, reading in bed wearing one of Mother's nightgowns, a floor-length, pale-pink, nylon empire-line with long, loose sleeves and a lace-covered bodice. It makes me feel like Guinevere in Camelot. Lost in my book, I am startled by a loud knock on the front door. I hear my brother answering it. A moment later, he appears at my bedroom door to announce, "There's a man here to see you." Standing in the open doorway is the man who had played the records in our living room after the party. In the daytime he resembles Michelangelo's David, his golden-blond hair curling around the nape of his neck like the statue. He wears a Liberty-print paisley shirt – unbuttoned to reveal a tanned, muscular chest – tucked loosely into tight-fitting, faded blue jeans. The sleeves of his mustard-coloured suede jacket have long fringes that sway when he moves. He has charisma to burn. "Hi," I say, hoping to sound offhand, but friendly.

“Young and in love”: Thompson with Leona (at left) and Bunkie in 1974. Credit:Weekly World News "My name is Jack. I would have come sooner," he says, "but I couldn't find your house again. I've come to invite you all to a party. It's for my birthday." I have relaxed by the time I've made coffee. Somehow we end up in my bedroom, where we sit and chat on my bed. Jack casually checks out the books that fill the shelves at the head and foot of my bed. I begin telling him about the one I am currently reading, an historical novel, Sinuhe the Egyptian. Jack listens, seemingly fascinated. He lights up a strong French cigarette and stays chatting with me for a long time. “We don’t own him”: Leona and Bunkie in 1971. Credit:courtesy of Bunkie King When he leaves, he reminds me to tell my mother and sister about his party at the end of August. I am so excited; I have actually been invited to an adult party. But my daydream is dashed when Mother refuses to allow me to go. She explains there will be drinking and, most likely, pot-smoking – it is 1969, after all.

Soon after the party, Jack returns for another visit. Mother is at work, so I make him coffee and we take our mugs and sit on the front step in the sun. Again, he seems to show interest in my thoughts and opinions. He comes by regularly after that, about once a week. I soak up his attention like a sponge. This is the first time in my life that someone is actually conversing with me and seriously listening to my ideas and beliefs about the world. And not just anyone, but a mature, handsome man whose full and undivided attention gives the impression that he respects my thoughts. Thompson with Bunkie’s horse, Bobo, in 1977. Credit:courtesy of Bunkie King After a couple of months, his visits suddenly stop. I mope around miserably, lose my appetite and can barely focus on my schoolwork. I assume Jack has lost interest in me or that I have done something wrong. Then I overhear Mother talking to my sister Maria. She explains that Le has run off with Jack; they have "eloped". Le has been in touch to let Mother know she is all right and that she has left David, her boyfriend of many years, whom everyone expected her to marry. I feel like an idiot, an immature child carried away by romantic fantasies. I'm embarrassed at my naive stupidity. Jack soon moves in with Le in a share house in Bank Street, directly behind Mother's house in Euroka Street. The proximity is convenient. His visits begin again – up to three times a week. I suppose Le knows he is coming; why would he keep it secret? After months of attention, Jack once more has my heart in his hands. When he starts to take me "parking" at Balls Head Reserve in his blue Datsun station wagon, I am in heaven. I experience my first kiss, the most intimate experience of my life thus far. His breath is warm against my cheek, then his soft, tender lips touch mine. Over the next few weeks, our sensual kissing moves on to being something a little more intimate. I give myself to him with an open heart, though I technically remain a virgin.

Le works shifts at a restaurant, sometimes from 2pm until midnight, which gives me the opportunity to spend time alone with Jack. One night, he and I are kissing and cuddling in their bedroom when Le bursts in the door and starts yelling, "What the hell are you doing?" He jumps up off the bed and tries to calm her down. I bolt out of the room, down the stairs, through the front door and out into the street. I hardly draw breath until I make it safely back to Mother's. I feel guilty. I know there's something wrong with what we've been doing. He's obviously Le's boyfriend and I feel bad for her, but I don't know how to give him up and just walk away. The next day, Jack and Le come over to discuss "the situation". It's a hot day, so we go outside and sit in the shade on the grass under the clothes line. I sit looking at the ground, scared of upsetting Le, as Jack suggests the possibility of a relationship that encompasses the three of us. He says we can make it work, because others have; it's about having love and understanding, being honest and open with each other and giving it a go. "We've found ourselves in this predicament, and the fact is I love you both." Within a few weeks, Jack convinces Le to allow him and me to spend a night together. I am already on the Pill. I've seen a doctor who was enlightened enough to reason that if I was going to be sexually active, then it was in my best interest to be using contraceptives. We end up spending our first night together at a cottage belonging to a friend of Jack's on Scotland Island at Pittwater, north of Sydney. It is sunset when we take the ferry across to the island and almost dark by the time we arrive at the beautiful wooden cabin on a hill. It is the ultimate romantic hideaway, but once inside I feel nervous and awkward. I wander around the living room, engrossed in the Asian art that fills the walls and admire the view through the big picture windows overlooking the water. Jack has made an effort to find the right venue, but that is where the fantasy ends. There is no cuddling on the couch, no tender kisses or the kind of caressing that was there during our courting sessions. We don't even eat before he undresses and climbs into bed.

My adolescent fantasies run wild as I undress and slip between the sheets. I am about to be engulfed by the physical and emotional passion of sharing myself with the man I love. But there is no acknowledgement of this gift we are about to share, no gentle caresses or soft words of love. It is all over fairly quickly; he turns away and is asleep within minutes. My expectations of making love for the first time are shattered. Confused by the lack of closeness and love, I reason it must be my inexperience. Perhaps he doesn't want to overwhelm me on my first time. Being young and in love, I resolve to accept him with or without intimacy and affection. Jack says he wants to be with me and that feeling of being wanted is so intoxicating that everything else pales in comparison. Le never says anything or shows any reaction to having her boyfriend sleep with her younger sister. I have no idea what discussion might have taken place between them afterwards – possibly none. I continue to visit their home on a regular basis and Jack continues to pick me up on his motorbike. With Jack's popularity at its height courtesy of his starring role in the TV series Spyforce, he buys 440 hectares of farmland in the hills above Coffs Harbour, on the NSW Mid-North Coast. One summer's afternoon, we pull into the clay driveway of the farm with little hilly paddocks backing onto virgin rainforest – it is love at first sight for all of us. The property is at 600 metres altitude: a short bushwalk to the escarpment offers a spectacular view over the Bellingen Valley. It also has a simple two-room farmhouse with a small kitchen and an even smaller lean-to area housing an old wood-burning stove. On our first overnight stay, we all sleep outside on the front verandah. It's so cold that we join two sleeping bags together and throw whatever we can find over the top – no sex, just four freezing people (a close friend is with us), desperately trying to stay warm. The farmhouse has no electricity or running water.

Jack buys a couple of beautiful, ornately painted antique kerosene lamps and Le and I enjoy turning the ramshackle dwelling into a home. The interior decoration is more her domain, while I make a rock pathway and a garden with ferns that I water throughout summer. I sleep in the only bedroom on a dozen tea chests packed full of "stuff". I cover the boxes with a carpet and put a mattress on top. Jack sleeps in that room with me or on the verandah with Le. He alternates nights between Le and me so there's no favouritism. Visitors stay in tents or wherever they can find a spot to make their beds. In the morning we usually cook breakfast outside, over an open fire. Jack finally has his own extended family of friends and lovers, his tribe. Mostly it is the same group of people, who are like family to me, too. Sometimes we stay up all night smoking dope and talking, moonlight shining on the moisture rising from the creek in a cloud that disperses slowly. To me, it seems like the earth is breathing. A new women's magazine, Cleo, is launching with a nude male centrefold. They want to make a big splash, but they are having trouble attracting a significant showbiz figure to bare all as the inaugural Mate of the Month. Many men agree, but then get cold feet. Time is running out; their deadline is looming. Eventually, Jack is offered the opportunity to pose, and he decides it will be a good chance to alter the general perception of him and change his image. Spyforce has fixed him in the public's mind as Erskine, a tough action man with a machine gun, a guy comfortable with random acts of violence. "I'd rather be a sex symbol than a kill symbol any day," Jack tells us. He sees the centrefold as a bit of fun and a good way to turn conventional stereotyping on its head: if it is "acceptable" for a woman to be photographed naked in magazines, then why not a man? But he doesn't want the beefcake pose on a beach that has been proposed. I look on with no small amount of interest as he agonises for days, trying to come up with an idea that reflects much more than just his physique. Jack is searching for something that is clever and different, something that shows he is a multi-faceted person: not macho and clichéd. In the end, he is photographed reclining on a sofa in a pose emulating a classic nude: Titian's Venus d'Urbino. The Cleo launch issue with the centrefold flies off the stands. Jack is now a sex symbol.

In 1972, I become pregnant for the first time. I am so fertile that whenever I slip up taking the Pill, I get pregnant immediately. It is only a year since abortion law was liberalised in NSW, but it has become fairly acceptable among women of my generation. I'm not emotionally disturbed by this choice, nor do I experience any moral dilemma regarding the destiny of the developing embryo. I believe that it is not the right time for me to have a baby. It's the first of three terminations I have over 15 years. I don't discuss the termination with Le. I keep wondering why it is that we never discuss anything meaningful. I believe it comes down to the fact that she doesn't actually want me around. Plus, given the rocky start to our threesome and my inferior position as the younger sister, I feel guilty about being there. As a result, I rarely question or confront her about anything. In late 1973, when the film Petersen is being shot with Jack as the lead, he can still walk down the street without everyone recognising him. Within a year, that changes completely. The film's advertising slogan reads: "Jack Thompson is Petersen." The film's sexual content becomes the focus of the marketing campaign. With his charisma and intelligence, Jack charms the journalists and quickly becomes a media darling. "I'm just as happy being a farmer," he protests during interviews, but admits his livelihood depends on publicity. He willingly accepts his role as a product to be marketed. I look on as Jack masters the art of seducing the media to further his career. Just as he applied himself to becoming a better actor, he dedicates himself to learning about the business of self-promotion. According to Jack, it's part of his job to be seen. At social functions, he flirts with everyone – men and women. Beyond his reputation as an actor, his appearance – tanned, blond, muscular – aids his seductiveness. Le and I usually stand by unobtrusively, waiting for the performance to finish so we can go home. As Jack's fame grows, journalists become curious about the nature of his threesome relationship. In October 1974, he co-operates with Sydney's Daily Telegraph for an article with the cheesy headline, "Jack and his Jills." In it, he is quoted as saying he sometimes feels "like a bone being fought over by two dogs".

No wonder "Jack the lad", as the media are calling him, starts to get abused on the street. Women see him and yell out, "Chauvinist pig!" He just thinks they're bourgeois prudes who are making a moral judgement. I don't agree with these women but I don't agree with Jack, either. For him, the issue is about having the personal freedom to break social taboos and live the bohemian lifestyle. It's all about free love. What he doesn't seem to comprehend, and the thing that I am beginning to see, is the aspect of Le and I losing our identities – we are no longer individuals. We are Jack's girls, collectively and possessively. In mid-1979, Jack works with Bruce Beresford on Breaker Morant, playing the role of lawyer Major J. F. Thomas. The following year, he gets the big news that Breaker Morant has been accepted into the official competition at the upcoming Cannes Film Festival – and his performance has been nominated for Best Supporting Actor in a feature film. Jack's sudden international fame inspires constant media intrusion into our private lives – journalists clamour for "sexy Jack Thompson stories" about the women in his life. He arranges for both of us to be interviewed and photographed for a feature by Nene King that will run in New Idea on May 10. He is quoted as saying, "I had someone the other day ask me if I was still living with the two sisters. And I wondered how an 11-year relationship could still be news … It only continues to be a relationship for the same reason as any relationship. There presumably must be a lot of trust, a lot of discussion and a lot of love." Trust? I hadn't trusted Jack since 1972, when Le and I arrived on the set of the TV series Boney to find him in the middle of a fling, and there is never a lot of discussion between any of us. I wonder what his definition of love is. Soon after, on June 14, in an article in Britain's Sunday Examiner-Express entitled "Lady-killer of Cannes", Jack completely distorts our reality by declaring, "The Women's Libbers attack me as a man dominating two compliant females. It is the other way around. I am an emotional slave to both of them. They are the free spirits." It's absurd, of course, for him to refer to Le and me as "free spirits". We're not empowered.

In Melbourne, I go along with Jack and Le to have lunch with the renowned Toorak hairdresser-socialite Lillian Frank. It becomes apparent that Jack's real motive is for Lillian to do a story on the happy threesome for her column in The Herald, a big-selling Melbourne newspaper. He succeeds. In the introduction to "The Sisters Jack Loves", published on July 5, Lillian states that we've been living together for 11 years in "an unusual arrangement, but deeply satisfying to all of them". Obviously, Lillian got that impression from us; Le and I have learnt how to tell a half-truth and make it sound wonderful. Lillian challenges us: "I didn't think two women – not even sisters – could even agree to share clothes, so how do you manage to share a man?" "But we don't feel as though we are sharing Jack," I reply. "He doesn't belong to either of us, so we can't share him. We don't own him. But we do love him. We are sharing time and life with him." I do genuinely have the ideal that nobody owns another. I believe that partners stay together because they hold similar ideals and love each other. While I don't feel that I own Jack, I suspect that he feels he owns me. We're not equal in that respect. Meanwhile, Jack is a compulsive Don Juan. The women he can't charm are few and far between. Greta Scacchi, then 24, is one of them, but I think she is mostly not interested because Jack is already with two women. They flirt a lot when Greta plays his love interest on the 1984 TV miniseries Waterfront, filmed in Melbourne.

Jack is now 43, yet makes it quite obvious to us that he is infatuated with this intelligent, divinely beautiful younger woman. There is constant flirting and innuendo going on between them. They share their own private jokes. Jack keeps telling Le and me how attracted he is to Greta and implies that we should be grateful he isn't running off with her, that the opportunity is there. I begin to question myself. What am I doing with my life? I have no money, career or family close by. Despite a growing feeling that I would like to have a child, I have recently had another termination. I realise I'm becoming more and more numb, just drifting along. I am devoid of any real passion. In anticipation of landing the role of King Saul in Bruce Beresford's 1985 film King David, Jack has grown an impressive beard and long hair. However, when Bruce is pressured by the studio to cast Edward Woodward as Saul, Jack utilises his hirsute appearance to accept a role in Flesh+Blood, a film set in medieval Italy and shot in Spain. After Jack completes wardrobe fittings in Madrid, we travel down to the main location in central Spain, the medieval town of Las Pedroñeras. One of the cast brings her young daughter with her on location, but without a nanny. I have seen the woman drinking in the bar while her daughter sleeps on the floor under a table. Their room is opposite mine and sometimes the little girl wanders in. She curls up beside me while I am reading. I brush her hair, enjoying the opportunity to nurture this lonely child. One day, when she is sleeping on my bed, her drunken mother bursts into the room shouting hysterically that we are incapable of behaving properly towards the girl. I hear words like "immoral", "people like you" and insinuations my conduct is inappropriate. She drags her fearful, confused daughter away.

Suddenly, this woman's accusations conjure up an abhorrent image that is foreign to how I think about myself and the relationship. A new awareness of public perceptions dawns on me; I feel cheap and dirty. Her accusations shatter my illusions that I am involved in a great romance. I am neither a cheap tart nor a deviant whore. I am in love, but I become conscious that I am also living an illusion. My dream is never going to be Jack's, Le's or this itinerant life we live. I want to go home. I sit quietly in the car as Jack drives me to Madrid airport. Knowing his uneasy relationship with punctuality, I chew my nails the entire two-hour journey. When we finally arrive, I drag my suitcase out of the boot and head into the terminal to get to the baggage drop-off counter before it closes. Suddenly, Jack grasps my shoulder and turns me to face him. "Show me your ticket," he says. "Why?" "I just need to check something."

Uncertain and confused, I hand him the ticket. Jack snatches it away. In a wrathful fury, he attempts to tear the ticket up. He then shoves it into his pocket and stands, glowering at me, just inches away. He is breathing hard, his face red. His gaze chills my insides as I ask, "What do you want me to do now?" "F… off!" he snaps. "What?" I am stunned. "Just f… off!" And with that, I am dismissed.

A wave of white fury engulfs me. I pick up my bag and storm out of the airport. Outside, I hail a cab and get in with no thought of where I am going or what I will do. Nobody who ever loved me could tell me to "F… off" in a foreign country and leave me with no money. I become conscious that I have no idea who Jack is. I feel relieved that the relationship is finally over and swear that I will never again be vulnerable to love. Edited extract from Somebody That I Used to Know: Love, Loss and Jack Thompson, by Bunkie King, published by Five Mile Press this week.