'We used a private eye to spy on our cheating husbands' Aimee Kitton can't quite pinpoint the moment she decided to hire a private detective to follow her husband. It began, as it so often does, with niggling doubts. Suddenly, he seemed colder and more distant and started switching off his phone when he was out at night. Doubt turned to suspicion when he began arriving home at 4am. When he became jumpy every time he got a a text message, she finally challenged him. He then accused her of being 'paranoid' - a label every woman dreads. For 32-year-old City trader Aimee, hiring a private eye was a way of taking back control. Instead of torturing herself, she made the call that would ultimately provide her with the brutal truth about her financier husband. Nothing but the truth: Maria Goldwin, Aimee Kitton and Karen Ellison hired private detectives to spy on their husbands 'My marriage was slipping away from me,' she says. 'Simon and I had been together for five years after meeting in 1998 on a training course when we worked for accountants Arthur Andersen. 'We bought a house together in London and married in July 2000. For two years after that, our relationship was rock solid. But by 2002, my suspicions were driving me to distraction. 'I was in pieces and needed to do something about it. With a friend, I searched on the internet to find a private detective to follow my husband and find out the truth.' Her actions may seem drastic, but according to a survey reported in the Mail this week, they are not uncommon. The number of private investigators hired to snoop on suspected adulterers has tripled in a year, according to a report published by law firm Grant Thornton. The survey, based on interviews with 100 divorce lawyers, reveals that nearly one in five couples involved in divorce cases hired an investigator - with a third more women than men using their services. That may be because men are more likely than women to be having an affair - in 86 per cent of all 2005 divorce cases, men were being petitioned for divorce by their wives on the grounds of adultery. Hiring an investigator may cost several thousand pounds, but an impending House of Lords ruling could turn family law on its head by allowing the conduct of both parties in a marriage to be taken into account when deciding upon financial settlements. Hard evidence, it seems, may soon convert to cash. 'In simple terms, committing adultery, the biggest reason behind divorce, could cost its perpetrator dearly,' says Andrea McLaren, a specialist in financial settlements on divorce. All that, however, was far from Aimee Kitton's mind when she instructed Douglas Pole at Metropolitan Investigations to follow Simon. At that stage, she was simply worried sick that her marriage was about to implode. She recalls: 'I handed over photographs of my husband, so Douglas knew who he was looking for.' Then she embarked on what she thought would be an agonising wait. But just a couple of hours into his first watch, the detective called to tell Aimee he was in London's Covent Garden taking photographs of Simon with a woman who was clearly his lover. 'I raced to the bar where they were, to witness it for myself,' says Aimee. 'I wanted to see what this woman looked like.' In fact, watching her husband kissing his young mistress, it occurred to Aimee that she was a carbon copy of herself ten years earlier. The 20-something woman, who turned out to be an office junior called Laura, was slim, blonde, pretty and exuded sexual confidence and ambition. 'She looked just like I did when we first met,' she says. 'I felt sick. My emotions were racing between anger and heartbreak as I watched them canoodling in the corner of the bar. 'After seven months of my husband telling me I was going mad, I had proof that I was right.' The problem, of course, is what to do with such information once you have it. In Aimee's case, it ensured there was no chance she would give her marriage - or her husband - a second chance. Heartbreak swiftly turned to a desire for revenge. 'My marriage was over. I wanted to file for divorce on the grounds of adultery and for that I needed evidence of more than them just kissing in public - that would only constitute unreasonable behaviour, in a court.' So, struggling to maintain her composure, she returned home and waited for her faithless husband to return. When he did, she simply told him she wanted space and was going to stay with a friend for a few days. 'I felt as if I was dying inside, but somehow I held it all together and managed to be as normal as possible. I was sure he'd take the opportunity to invite this woman back to our house - and I was right. I sneaked back when he was at work two days later and although he'd tried to do a clean-up job, not much gets past a suspicious wife.' The first thing she noticed was a pile of rented chick flickDVDs in the sitting room - films her husband would never usually watch. 'It may seem a small thing, but it was an example of the intimacy they were sharing in my house. I was devastated. But the final insult was walking into the spare bedroom, a room we rarely used, to find the bed hadn't been made properly. They had actually been having sex in my spare bedroom. 'I was hysterical and picked up the phone to the detective again.' This time, he fitted a listening device inside the house. That night, she sat with him in his car, waiting for four hours until her husband's lover arrived at midnight. 'It was sheer hell,' she says. 'We heard her say: "You're the man of my dreams, Simon, but when are you going to leave her and be with me?" 'As Simon avoided answering her questions, they got into a bit of an argument which then led to passionate sex.' Sitting in the car outside her home, Aimee heard everything. 'It was the most painful experience of my life, but it was also an almighty release. At last I knew I wasn't mad or paranoid or ridiculous, or any of those other things my husband had told me I was.'