I spent three years engaged to a powerful man who, I later found out, paid for sex whenever he got the chance. I'm now dubious about the “addiction” argument because during those three years I heard it all. He blamed his addiction on every important or iconic female in his life, from his mother to Mary Poppins, on every girlfriend he had ever had and every pop star he had ever dreamt about. For a while I believed him, and stood by him as he went through a programme for sex addicts. Finally, after no change, a lot more pain, betrayal and HIV tests, I figured it out:he did it simply because he wanted to and, more importantly, because he believed that as a successful - ie, wealthy - man he had earned the right to do it.

Unbeknown to me, he loved having sex with strangers and - like Spitzer - the riskier, the better. Unlike Spitzer, however, he didn't stick to beautiful female prostitutes; he also used rent boys, frequented gay saunas and was a member of at least 20 sex-seeking websites. As his success grew, money became an increasing feature in his sexual adventures.

My former partner works in the financial world. He is tall, wealthy, successful and powerful. Many people depend directly on him for their livelihoods and many other colleagues profit from his business acumen. He exists in a world where he is surrounded by people who look up to him, depend on him and have faith in him.He believes he has earned the right, outside the workplace, to do what he wants - whatever he wants - and his money has certainly helped to persuade those around him not to challenge that view.

When we were together he insisted that as long as he was a good partner to me while he was with me, whatever he did in his own time was up to him - “I have a right to a private life!” he would shout when we argued about his infidelities. Over time I learnt that in his world ugly, sagging, fiftysomething husbands and fathers saw it as their right as Successful Men (financial success being the only valid measure) to buy attractive girls - often as young as their own grown-up children - for sex: girls who, were money not involved, wouldn't have given these men a first glance, let alone a second. Let's face it: even Spitzer wouldn't have got “Kristen” into bed if he had depended on his looks to entice her.

But it isn't just the sex these men get off on, is it? Isn't it also a fact that they have the power to buy whatever they like? I have spent many tedious hours listening to clichéd discussions about top-of-the-line cars and yachts over dinner tables in the best restaurants in London. Most wealthy men want to spend their money in ways that underline their wealth, their power, their manhood. And what's more powerful than being able to buy another human being (especially one like Kristen who, like an Aston Martin, is beautiful enough to be unattainable to most people), to own them for a couple of hours and to have the power to get them to do whatever you want?

Certainly for my ex, the wealthier his success made him, the more money became a part of his sexual preference. He joined Sugardaddy.com and DateAMillionaire - he even advertised on the internet for male and female students 30 years his junior who he would “help” financially for sex. In his ads he didn't highlight his looks or personality but would describe himself as a “tall, successful businessman” with a “generous” nature. He didn't need to pay for sex, especially sex with strangers. I believe that he liked paying for sex because that buying power - the temporary rule it gave him over that other person - felt good and added an extra, thrilling dimension.

I don't suppose that my ex is that unusual. A friend of mine who is a futures trader says that brokers routinely offer prostitutes to clients as lightly as free samples at a cosmetics counter. A female friend who is a partner in a City firm told me that many men she works with sleep with prostitutes, and it doesn't really bother her. She believes that some do it for a laugh, others as stress relief, allowing them some space where, for a change, they are not responsible. I'm sure thatall this is true for some men, but it still bothers me. It bothers me because in most cases there will be a wife or partner who is being deceived, and possibly even having her health put at risk.

When I used to argue with my ex about his cheating I would say: “It's up to you what you do with your life, but by lying to me you're not giving me a real choice about what I'm doing with mine.” I had no strong view about men sleeping with prostitutes, being gay or bisexual, other than that I wouldn't want my partner to do those things: my issue is with wasting someone else's life. For Silda Wall Spitzer, I would guess thatit won't be the extramarital sex that's hurting her as much as the years she has spent being duped into living a lie, not knowing the man to whom she is married and, worst of all, suddenly realising that he sees her in a completely different way from how she thought he did - someone he can cheat on, someone he can deceive, someone whose time he doesn't value enough not to waste, someone he doesn't respect enough to be truthful to.

But is this kind of high-risk behaviour - whereby careers, families, whole lives may be ruined if the truth outs - borne of the kind of arrogance that breeds a feeling of invincibility or is it, as John X claims in his article, a genuine sickness, a kind of sexual addiction? Whether such addiction really exists is still a matter of dispute in psychological circles, but if the symptoms of a racing pulse, heavy breathing, the inability - or a refusal - to say no, the highs and lows and the guilt make a person an addict, then the whole world is addicted to something.

John X says that all addicts “crave that headspace where nothing else matters”. We all do after we've had a bad day, and I suspect that women such as Silda Wall Spitzer, who have given up their own careers and identities to follow their husbands crave that space even more.

John X says that he is now married to a woman whom he would never betray. Please don't, Mr X: it's the lies, not the sex, that do the damage