'For 5 years I had an affair with a married man. As soon as I was single, he left his wife for someone else.'

When you've finished reading this, you'll probably think I deserved what I got. And I would have to say, I agree with you.

Let me set the scene. I was married to John*. My best friend, Julie*, was married to Dan*. Dan and John were also close friends, and we all lived on the same street.

Cozy, right? We even went on holidays together.

When the affair started, I was extremely depressed and unhappy in my life. I couldn't work out why, but I knew I needed more. I was comfortable and settled, but I was also bored.

I felt like nothing more than a wife and a stay-at-home mum and I was starting to get the sense that this simply wasn't the life for me.

Watch: MM Confessions: I wish I'd never said. Post continues after video.

Dan gave me attention. He was interested in what I had to say. It wasn't mundane. And it was never actually about the sex, to be honest — the man wasn't that attractive. I wanted him because he cared (or so I thought).

We spoke everyday - Dan had a separate phone for our messages, but I didn't, which almost brought me undone a few times.

We only actually met up for sex about once a month. We both ran our own businesses so would fake meetings, then get together.

I got really good a compartmentalizing what I was doing. And whenever I felt guilty, I reminded myself how much my husband didn't appreciate me or treat me well.

To be clear — I am NOT trying to justify my behaviour. In fact, if I had my time again, I would make very different decisions, and I know it is a path I will never tread again.

After five years, I cooled things with Dan, but we still spoke at least once a week.

He was there for me when I finally decided to end my marriage.

But soon after that, I was on the phone to him when I realised he sounded… "off". I asked him what was wrong, and it all just spilled out.

"I'm in love with another woman and I'm going to leave Julie," he said.

To say I was shell-shocked would be an understatement.

Clearly, he'd been having another affair. I don't know when or how it started, I don't know where and when they met up, I don't know what they talked about.

And I don't know how that particular affair went from secret tryst to him leaving his marriage, when mine did not.

And I didn't want to know.

I couldn't understand why it wasn't me. Why hadn't I been the one he was leaving his wife for? By this time, my marriage had ended, and I was a free agent - so you can imagine what was going through my mind.

It hit me like a ton of bricks.

And when Dan actually left Julie, eventually marrying the other woman, everything just blew up.

Two of Jenny's three children refused to have a relationship with her, and one of Dan's children was the same. The news split the close-knit friendship circle squarely down the middle, with friendships of 30 years irrevocably broken.

And Julie?

Bitter.

As you would well imagine.

Although our affair never came to light, I'm no longer a part of that friendships circle - Dan has made sure of that. I think he realises how much damage I could cause if I were to open my mouth to his new wife.

And while I am actually glad I'm out of that toxic circle, I do worry.

Because while I wouldn't say anything to his new wife, I'm pretty sure a leopard who has shown his spots over and over and over again… isn't going to change.

Feature Image: Getty.

*names have been changed