'I never thought I'd sleep with a married man. Then I received an unexpected text.'

As told to Ann DeGrey.

I'd been single for five years and feeling quite desperate for a new love in my life. After a bad breakup and a string of awful dates, ranging from disappointing to disastrous, I'd honestly stopped expecting anything exciting to happen.

But then Angus* came into my life.

He worked in the office two floors up from mine, though we both worked for the same organisation. He was absolutely gorgeous and just my type; tall, with dark hair, a beard and tattoos. Yes, he looked like the office "bad boy." But he was always so charming and quick-witted.

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When I found out he was married, my heart sank! But we got on very well and there was an insane amount of chemistry between us. I kept telling myself, "If only he wasn't married!" I used to feel guilty just having a crush on him. I told myself it was harmless. He was off-limits, and I wasn't the type of woman to cross that line.

So when he started paying me more attention — lingering longer by my desk, messaging me late at night about the TV series we were both watching — I was flattered, yes, but also confused. Was he really trying to get close to me?

He asked me to join him for lunch one day and that's when he told me things weren't working with his wife, that they were more like friends now, that he didn't feel "seen" anymore.

That night, he texted me to say he had feelings for me and that was the beginning of it all.

We went out for drinks the following night and he came back to my apartment where we fell into bed. The sex was fantastic because by that stage I was really falling for him. And that's how our affair started.

I hated using that word, but there it was. I'd become the woman I promised myself I'd never be.

He would come over on "work trips," text me from the bathroom at his house, and he made a promise that one day soon, he'd leave her.

He said I made him feel alive again. That he hadn't felt this way in years. And I believed him. I really thought I was different.

Then one Friday evening, everything changed. A group of us from the office had gone out for drinks to celebrate a coworker's birthday.

Angus said he couldn't make it as he was catching up with his cousin. But later that night, I saw him when our group moved to a different bar. And there he was — not with a cousin, he was with a much younger colleague called Sally*.

Sally was very pretty and giggled a lot. That's about all I knew of her. They were sitting close together, laughing over cocktails like it was the most normal thing in the world. She was gazing at him with adoration. I knew that look. I'd seen it before — on me.

I didn't want to humiliate myself by confronting them, so I waited until the next morning to pull her aside.

"Are you seeing Angus too?"

"You mean besides his wife?" she asked, like it was nothing. I must've looked shocked because she shrugged and said that she knew about me, and she didn't care.

"It's just an affair. That's all. He's not leaving his wife. You know that, right?"

I walked away feeling like a complete idiot. I'd spent months making excuses for him, convincing myself that our connection was special, that he was stuck in a miserable marriage, and I was just helping him find his way out. Instead, I was one of two women he was playing with. Yet, clearly, I was the bigger idiot because I believed that what we had was real.

At least Sally called it out for what it was; just an affair.

I ended things that same day. I texted Angus, asking him not to contact me again. He called me a couple of times and even showed up at my apartment once. I didn't respond.

Now, I'm left sitting with this pit in my stomach; not just from heartbreak, but from shame.

And yet, one question keeps circling in my mind: Should I tell his wife that he wasn't having an affair with just one woman — there were two of us? As far as I knew, she had no idea, and probably believes her husband is always working late or away for business reasons.

Part of me wants to protect her, to tell her what I wish someone had told me. But I realise it's not really my place. I've already played a part in hurting her. I don't know if more truth will help or just add to the wreckage.

I know I was wrong to get involved with a married man. Maybe I got what I deserved.

But what stings most is how easily he walked away, quite unbothered.

While I was left picking up the pieces.

The author of this article is known to Mamamia but has chosen to remain anonymous for privacy reasons.

Feature: Getty.