Last year, I came out to the only important people left in my life who were still oblivious to my sexuality: my three children. I was 41 and had known I was gay since before I'd heard that word, so you might think I'd taken my own sweet time about this. It's not quite that simple. I'm an old hand at this coming-out lark. In fact, I feel a bit of a fraud hitching a ride now on the gay bandwagon. Put it this way: had I filmed my first coming-out, as Tom Daley did with his, it would have been recorded not on a mobile phone but on a chunky video camera the size of a cereal box. Uploading it to YouTube would have been pointless because neither uploading nor YouTube had been invented in 1985.

My confidantes when I came out at the age of 14 were two female friends at an unremarkable Essex comprehensive. Given that I was a less-than-macho drama student, those friends in biology class did a good job of feigning ignorance about the nature of the confession to which I was building up over the course of an hour. Eventually I babbled the words "I'm gay!" before bolting from the room.

They caught up with me later and assured me that what I'd done was brave and that they wouldn't tell anyone else, approximately an hour after telling everyone else.

On second thoughts, it's unfair to describe my comprehensive school as unremarkable. Certainly it's amazing to realise that I was never bullied or harassed. The one species of opposition I experienced at school came from a teacher and was cleverly disguised as sympathy. Not long before coming out to my friends, I had broached the subject of my sexuality in an essay.

My teacher summoned me to her office, where she made understanding noises before recommending that we bin the document and pretend it had never been written. I had entrusted to her my coming-out statement and her response was to rain on my incipient Pride parade: one of those apparently light downpours that you later find has soaked you to the skin.

Her fear was that my classmates would be spiteful if they found out my secret, when in fact the nastiest thing that happened was seeing her rip up the essay I had spent days working on and even longer mustering the courage to write. (Nastier in its way than being insulted by middle-aged male commuters, a group on whom I could depend for homophobic abuse as a teenager.)

My peers restricted their attention instead to a solitary joke comparing me to Frank Bruno, which hinged on the use of the word "ring" as a double entendre. I rather cherished being the butt of that gag, as it depended for its success on the idea that I was sexually active. When you're a 14-year-old virgin, the widespread assumption that you're getting lots of action provides some footling compensation for the fact that you're not.

Ryan and his younger daughter, Edith.

Throughout adolescence I was only involved with and attracted to other boys, even if they never graduated into take-home boyfriends. But the message had been subtly conveyed to me that being gay was not a desirable course to take. My parents had transmitted signals of disapproval since I was five or six, when I was a keen reader of DC Comics, with their plentiful ads for bodybuilding courses. My mother would reach over my shoulder to turn the page if she felt I was lingering too long on pictures of muscle Marys in clingy trunks. Imagine how thrilled she and my father were when I went on to show an interest in the performing arts in my early teens or absent-mindedly threw my "Stop Clause 28" T-shirt in the family wash.

But I can't blame those adults for my decision to abandon the person I knew I was. A likelier deterrent was fear of loneliness. Growing up in a tumbleweed village I perhaps mistook the sense of isolation that many teenagers feel, for a condition specific to being me, to being gay. It's that state of mind, I think, that made me grab at affection in whatever form it came.

The chronology of what followed is straightforward, even if the emotional element is opaque. A year after attending my first Pride march, and a few months shy of my 18th birthday, I tumbled into a relationship with my closest female friend. We later had two children before breaking up when I was 23. Some time after that, I began a relationship with another female friend; we had a daughter. Those women were the only girlfriends I've had and the only women I've been attracted to. It just so happens that I made both of them pregnant, which has tended not to be the case when I've slept with men.

Neither of those relationships was bogus – these women were girlfriends, not beards or alibis. Despite that, I felt at times like an undercover agent gone rogue. I told myself I was a gay man who happened to have fallen in love with a woman – twice. People do get press-ganged into straight relationships, but that isn't my story at all; whatever the underlying reasons, I went willingly. Nor did my girlfriends have any illusions. They had been my intimates long before they were my partners and had listened to me whining about whichever hot guy hadn't returned my gaze or my phone-call that week.

My relationships with women didn't founder solely because of my sexuality, though it was obviously a factor. Whenever we went through our periodic break-ups, I would revert immediately to my factory settings – relationships with men – before returning to try to fix things, bringing with me each time the same unresolved struggle. One of my girlfriends remarked that I always had one foot out of the door. As a father I hope I am loving and loyal, but as a partner to women my commitment was provisional. Shortly after my first child was born, I attended a job interview where I responded to a casual question about my domestic circumstances with a revealingly noncommittal answer: "I live with my girlfriend – at the moment."

But moments accumulate into lives. That's how a gay man can come to spend a chunk of his adulthood in straight relationships.

Those years feel now like a perverse captivity in which I was jailer as well as prisoner. I could knuckle under as long as I didn't catch a glimpse of the outside world. One weekend, I saw two men of my age holding hands and nuzzling as they strolled among the stalls at Borough market. I seethed with envy, indignant that they enjoyed the honest freedom I had denied myself. One of them noticed me staring joylessly and looked perturbed. I didn't care. All I could think was: I want that.

The life I longed for had become like a motorway exit that I'd missed; I told myself it was simply a matter of keeping my foot to the floor until the next exit or the one after that.

I learned to take refuge in an alternate existence in my imagination, one where I still had my children but was openly gay. Fantasies are essential to life but they can't very well be a substitute for it without mental illness creeping in. On my bleakest days, I found myself thinking: at least I'll make the right choice on my next go around. The "next go" meaning my next life. At the time, it felt like a story I recited so I didn't go under. From this distance, it's a dead ringer for the delusional or worse.

Ryan with Rosie when she was a toddler.

I had already been single for some time when I decided last year to tell my children I was gay. The catalyst was meeting a man with whom I could imagine having more than just a fling – "imagine" being the operative word here, as this turned out to be a romance that existed largely in my mind.

I knew that coming out to my children could not be done in one fell swoop. Getting them all in the same place at the same time requires extensive planning and synchronised watches, and I was determined that my confession should appear as nonchalant as possible. I delivered a dry-run speech to my father, whose ignorance of my private life was more or less theoretical. It ran as follows: "You probably know this because everyone else in the family does anyway so there's really no need to say it but I just wanted to say: I'm gay."

This outpouring, delivered without any space between the words, occurred while I followed him around as he watered the plants. So much for nonchalance. Never an effusive man, his response (a nod, followed by: "Whatever makes you happy") was the equivalent of a whoop and a "Go, girl!"

I was no less of a stumblebum with my two daughters, who are 20 and 13, and my 19-year-old son, each of whom is cooler than I ever dreamed of being. I suspected that my elder daughter would be nonplussed, possibly even approving. She's a photography student who specialises in portraits of drag queens and has entrée to gay clubs I've never heard of. In a bustling restaurant, I succeeded in coming out to her across the quesadillas.

Unfortunately it was so noisy that she had to shout my confession back at me for clarification ("Did you just say that, apart from two girlfriends, you've always been gay?") at the precise moment that the deafening chatter around us dropped in volume. Had I seen that happen on screen, I would have dismissed it as a hackneyed comic device. Life is always turning into a bad BBC3 sitcom when you dreamed it would be Girls.

Coming out to my younger daughter was more complicated. Her mother and I had been estranged for far longer than she'd realised, and had tried to maintain the facade of still being a family, so it was actually a "We're not together any more" conversation that morphed unexpectedly into a coming out: two shocks for the price of one. About the first she was heartbreakingly sanguine. "Oh that," she shrugged. "I knew that was going to happen."

Then her mother blurted out: "Dad's seeing someone."

My eyes popped. This wasn't what we had agreed would happen.

"Really?" our daughter asked.

"Um. Well, no. I mean, I like someone but I'm not seeing …"

"Is it a boy or a girl?"

Well. That was unexpected. "It's, it's … It's a boy. Not a boy. A male. A man."

"Really? Really?"

Ryan and his son Barney.

This, you could see her thinking, was more like it. Now we're cooking! Parents break up all the time but this – this was news. For a few fleeting seconds I was exotic in her eyes. "You always seemed so straight," she said by way of clarification. "Not straight but … boring."

I had wondered how to tell her brother when he next came to stay, but that decision was taken out of my hands too. During a conversation we were all having on the London Underground about the Mighty Boosh, my younger daughter announced mischievously: "Dad only likes it because he fancies Naboo." (You must remember Naboo: the teensy-weensy shaman, cute and hairy as a marmoset.)

My son smirked. Feeling nearby heads turning in the tube carriage, I once again went into stammering mode. "Oh," my daughter said mock-innocently, "haven't you told him yet?" My son's response was the same all-purpose one with which this most unsurprisable of young men greets everything: "S'all gravy."

The phrase "taking it in his stride" does not adequately suggest how blase he is. Only a few weeks ago, for example, I found myself receiving sympathetic advice from him when I confessed to feeling nervous about meeting my boyfriend's family for the first time.

The difference between being gay in the 1980s and now is immeasurable, and not merely for those of us who have fathered three children in the interim. Back then, shame had so many outlets for a gay teenager in Britain. Those days are numbered, if not yet over, and that makes me happy. But I also feel a niggling strain of jealousy, even resentment, that it wasn't as easy for me the first time around as it is today for many people.

It's only natural in my selfish way to wish it had happened when I needed that affirmation from the world – just as my delight that my parents accept me now doesn't stop me wishing that they could have put themselves out of step with their contemporaries when I most needed them to. It's easy enough to say that ice-cream is awesome when everyone else has come around to loving ice-cream too. Less so when the whole world thinks soup is king.