The first time that I met Gregory, I felt I'd known him for ever. He gave me my first job with total faith in my ability. I was comfortable in his company; we had shared interests and outlooks. He was a decade older, married with children and I was with my boyfriend Simon. If we'd been free, we would have gone for it.

I moved jobs and although Gregory's friendship endured over the next ten years, contact waned when I married Simon and had a baby. Simon was stable, a great friend who helped me through years of family losses, but he wasn't my soulmate. In 2005, Gregory e-mailed to invite me on a new project. Nothing had changed; we slipped back into banter, sharing problems and supporting each other. Over the next six months our messages became intense and flirtatious. I tried not to fall for him, but receiving 20 e-mails a day became my emotional escape. He was supremely attractive, but I realised I really loved him. We met and consummated the affair. We weren't planning to leave our families, but wanted each other. It was wrong, but felt right and we agreed to meet once a month.

Then, a couple of weeks later, he stopped writing and didn't answer my messages. After three days I e-mailed a colleague on our project and was told that Gregory had died of a heart attack. The pain was searing. I've never experienced such despair. Although I told Simon of his death, I had to contain my grief. I didn't want to admit the affair. At the funeral, it was good to be among others who cherished Gregory. Because no one knew of our affair, I had no platform for my grief. On the first anniversary of his death I started a course of therapy. I told Simon I had work issues, that I felt depressed, which he accepted. The counselling allows me to grieve openly. Without it, I might lose my sanity.

I still avoid meeting new people because my grief is so consuming. I hate being duplicitous with my family, but I am trying to protect them. The few people I've confided in give me an outlet, but I risk being judged for my infidelity.

After the funeral, Gregory's wife asked a mutual friend to sever all contact with me; I believe she discovered our affair. My guilt is focused on her, rather than Simon, because I feel widowed too. I worry that in the long term, living a lie will affect my physical as well as mental health. Losing Gregory, and grieving inwardly, has posed a bigger threat than my affair would have done. I may tell Simon the truth, so he understands why I need to leave him: I can't spend the rest of my life with this man, who isn't Gregory.

Do you have a secret? E-mail: familysecrets@thetimes.co.uk

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