When I first saw him it was like a blow to the gut. Peter has that tall, rangy appeal that can turn on the coolest of women. We dated when I was 40 and he was 55. Our love affair was a secret: he had a 35-year marriage and grown-up children; I had just come out of a long relationship. After 18 months he got divorced and we were married in the Netherlands.

We divided our time between England and the Continent. For more than a decade, the sex was terrific. He had been something of a Casanova, so I was rather surprised when he said one day: “Sexually, you woke me up. Other women lie back and wait for it to happen.” If he was rather a conventional lover, shy of nudity and only happy making love in bed, I didn't worry. He was affectionate, often hugging me for no reason. Then in March this year, as he approached 68, his erections became difficult. Making love felt as if he were spooning a soft-boiled egg into me. I made light of it in the knowledge that, with age, men often suffer such problems.

For three months, sex was intermittent. One day I came home to find him watching a pornographic DVD. “I wanted to see if it had any effect,” he said guiltily, switching it off. “And did it?” “No.”

For weeks Peter was anxious, withdrawn and depressed. He hardly spoke. Now there was no hugging. When sex didn't work, he would mutter: “I'm a failure.” “No,” I'd reply, “relax, there are many ways to skin a cat.” But Peter was a conventional man. For him it was all or nothing. The man I loved was changing. I tried to help him to talk. He was terrified of ageing, admitting: “I never thought it would happen to me.”

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BACKGROUND

• What to do about painful erections

• Pill with too much thrill?

• Tempted to hire a male escort

• Cirrhosis of the liver causes erectile dysfunction

BACKGROUND

• Can't take the pressure?

• He pounces, and I panic

• Impotence

I spoke to various male friends, all of whom reacted with great sympathy - for Peter. “He must be in such despair,” said one. “He feels that he has lost his manhood,” added another. “Oh, he is clearly in such pain. Poor Peter.”

Younger men asked his age and then, to my surprise, each one counted how many more years of “uplift” he might have. All identified with him immediately. Not one asked me what I was feeling about the lack of sex or the emotional separation. I learnt that erection is a crucial and central part of the male experience and that men judge themselves on it. We all know that men are obsessed with size, but I hadn't realised how important it is for them to be able to perform at will.

I asked Peter to see the doctor about erectile dysfunction, which can be a symptom of other health problems. Peter is healthy, slim and has always been a keen sportsman. The NHS doctor assessed him as a possible Viagra candidate but, as he takes statins to reduce his cholesterol, the magic drug was considered too risky.

Peter was asked if he had erections during the night or first thing in the morning. The answer was yes. Therefore the doctor judged that “as the mechanics still function, extra medication should be avoided”.

Despite being told that he had no physical impediment, his depression continued. I wondered if it was psychological. Perhaps he had gone off me? If this were the case the porn video would have done the trick. The fact that it didn't work for him depressed him even more.

I researched further. The NHS doctor was correct. I read about three drugs prescribed for erectile dysfunction: Viagra, Cialis and Levitra. Cialis lasts the longest. First, there are the stated possible sideeffects of headache, upset stomach, nasal congestion, vision changes and back pain with Cialis. But even more worrying was the US Food and Drug Administration (FDA) reports on post-Viagra deaths. From March to November l998, when six million people took Viagra, the FDA reported “130 deaths after being prescribed this drug, of which 77 had cardiovascular events”. Most of those who died had one or more “risk factors”.

As the NHS doctor wasn't prescribing, Peter could certainly buy Viagra online - but the doctor told him that self-prescribing was very dangerous. Peter relayed this news to me with a certain amount of resignation. And, although he was assured that there was nothing mechanically wrong with him, his mood remained low.

We were used to good sex three times a week and now it was about once every three weeks. I began to absorb his anxiety and, for the first time in my life, sex stopped being playful and fun. The gorgeous, sexy man I had married was transforming into a sad introvert. There was no intimacy on any level. I felt isolated and sexually frustrated. Looking back, I didn't realise how lucky I was.

Peter returned to the Netherlands to see family and asked me to come out for a weekend to his flat. I arrived on the Friday and that night there was certainly no dysfunction. In fact, there was a missile, grown to twice its normal size. What should have been pleasurable was almost painful.

This was certainly not lovemaking, it was more of an attack. But his relief was manifest, his self-satisfaction immense. “Did you take Viagra?” I asked, knowing the answer. He ignored my question and went to sleep. The next morning his erection seemed to have a life of its own. It was as if the man had disappeared behind it. There was no tenderness or kissing, only “I must have you now”. This was the opposite of sex. It was a clinical experiment.

Over breakfast he admitted to seeing a Dutch doctor, who had prescribed Cialis. “It's not Viagra,” he said, aware that I was worried about the health implications. But the leaflet inside the packet confirmed that it is a sister product with the same contra-indications. It is dangerous for men with heart conditions, liver or kidney problems. It can affect the eyes, increasing glare or changing colour-awareness.

While I was worrying about Viagra, Woman's Hour on Radio 4 broadcast a programme to celebrate the tenth anniversary of the drug's launch. A couple in their seventies praised the way it had rejuvenated their sex life - but still I wasn't convinced.

When I asked friends about this, Carol, a sexually active woman in her mid-sixties, said: “My partner couldn't maintain an erection, and soon his problem became mine. We tried vacuum pumps and that was grim and uncomfortable, then progressed to Viagra. It made him slightly woozy, but over time he learnt to be a more attentive lover. Eventually the Viagra, and both of us working at it, meant that occasionally we had good mutual sex.”

The relationship did not last, however. Perhaps working at sex is just too unsexy. Helena Woddis, a psychosexual therapist, confirms that the woman on the receiving end of Viagra or similar drugs can feel used and disappointed by the mechanical sex that the pills often produce.

I returned to the NHS doctor to tell him that Peter was taking Cialis. First he was furious, then he laughed. “Well, I said that if he took any form of Viagra it would kill him. But at least he'll die smiling,” he said.

My husband, a father and grandfather, is prepared to put his life on the line to prove that he can still have sex. He may die with a smile on his face, but there won't be one on mine.

Blue pills online

Men desperate to cure their impotence were given hope ten years ago with the arrival of Viagra. But many were ineligible for it on the NHS, and so were forced to trawl the internet for the “magic” blue pills.

Doctors have been struck off for prescribing erectile dysfunction drugs online. But now Lloyds pharmacy and the sexual health website Dr Thom will allow men to buy authentic pills over the net without having to see a GP. Site visitors fill out a questionnaire and, if appropriate, a doctor will post them a trial course of up to eight tablets, at £45 for four tablets of Viagra, Cialis or Levitra.

Viagra, made by Pfizer, appeared on the market after chemists found that it had little effect on angina, for which it was developed, but did induce erections. It works by inhibiting an enzyme, cGMP, that regulates blood flow to the penis, and is used by about 25 million men worldwide.

According to Lloyds pharmacy, about 40 per cent of men aged over 40 in the UK suffer from erectile dysfunction.

Doctors do not prescribe Viagra to men with low blood pressure, or those who take certain heart drugs.

Research has suggested that Viagra could promote blood clots and may be a danger for those at risk of heart disease and stroke. Pfizer denies this.

Only 48 per cent of men in the UK who suffer with erectile dysfunction qualify for NHS treatment. About 4.2 million have either to pay for treatment or miss out.

Alexandra Blair

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