In August 2004, I filed for divorce from my husband Michael, a carpet fitter. We had two children, Philip, five, and Victor, one, but things weren't working between us.

After we split up, I started to go out a bit more. One evening, after finishing at the catering company where I worked, I met a girlfriend in a pub in Aalbaek, a tiny fishing village in the north of Denmark, a few miles from where I live. A handsome blond man called Tommy came over to talk to me. He worked in Aalbaek, in the fishing industry. We got on well, and that autumn we began to see each other. But I was wary about getting into another relationship.

Michael had always hoped for a reunion and on New Year's Day, after a long fight, we ended up in bed. I didn't think of using contraception – we had needed help to conceive our first son and we were about to do the same when I became pregnant with our second.

Less than two days later, I slept with Tommy. I ought to have used protection, but I got caught up in the heat of things. The incident with Michael had been a one-off and I was determined for it stay that way. I didn't tell Tommy – we were still in the early stages of our relationship. Several months later, I went to the doctor. I had been feeling unwell for weeks – sick and bloated. He confirmed what I had been dreading: I was pregnant. But that wasn't all – I was expecting twins.

I told both men that I didn't know who the father was. It was an emotionally chaotic period. Michael was hoping two more children would bring our marriage back together, while Tommy had always wanted a family and was desperate for the twins to be his. They were angry I had slept with both of them. I didn't want to be with Michael and I still had feelings for Tommy, but while I was pregnant I decided to think of myself as single. It seemed the least complicated option. I was living on my own when the boys arrived on 23 August, 2005.

As we already had two children together, Michael had been very involved in my life while I was carrying the twins. It seemed right that he should be there for the delivery. The birth went well but it was soon clear the boys were not alike. Marcus's face was round and his hair was red; Lucas was fair and his face was long. A doctor confirmed that there was a one in 13,000 chance the twins could have different fathers, and a couple of weeks after the boys were born, my mother finally said aloud what we had all been thinking – that Marcus looked like Michael, and Lucas like Tommy. I felt overwhelmed. The shock of suddenly having two babies to care for meant I couldn't face dealing with the issue of their paternity straight away. Both men were so desperate to be the father, it seemed easier for the time being to continue thinking they both were, rather than risk crushing one of them by finding out for sure.

As a result, the tension between Tommy and Michael seemed to ease and I felt as though I was able to re-establish my relationship with Tommy. Things between us grew stronger, and after six months we decided to move in together. A while later, Tommy bumped into my brother, who was having a drink with Michael. They had a couple of beers together and, over the course of the evening, the rivalry and bitterness that had been between them was soothed. A year after the birth, we decided we were all ready to take the DNA test.

After a few tense weeks, a letter arrived stating that there was a 99.9% likelihood that Lucas and Marcus did not have the same biological father. Even though it was what we had all suspected, it was a huge relief. Our family and friends were very supportive – we had always been open about the situation.

Today, Marcus is a short, thickset redhead with a lot of energy, just like his father. Lucas is taller, broader and blond, and has a very gentle manner, just like his dad. Michael's three boys spend every other weekend with him and sometimes Michael will take Lucas, too. Thankfully, all four boys get on brilliantly.

Tommy and Michael are now friends. Although it hasn't been easy, we all feel lucky to have had such a strange thing happen to us.

• As told to Marianne With Bindslev.

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