"My partner cheated on me with his ex-wife."

Image via Universal Studios.

Before you’ve been cheated on for the first time, you think that cheating is a total deal breaker. You swear to your friends that if anyone was every stupid enough to cheat on you, then it was over, instantly. There were no second chances.

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I thought this too, until I was cheated on. I thought that I would move on without a second glance. Unfortunately my situation was a little more complicated because my boyfriend of four years chose to cheat on me with his ex-wife, and it was his 12-year-old son who told me about it.

When I told my boyfriend I knew he’d cheated on me with his ex, he collapsed onto the road and vomited.

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See what I mean by complicated?

When I first started dating him he told me he was divorced, that it was amicable and that they got along really well. They weren’t divorced, but in his mind it was just a matter of paperwork. It was amicable, until I came along. They got along really well, except when they fell into the familiar patterns of their failed 10-year-marriage by fighting and flirting. (Post continues after gallery).

My first sign that something was up was when I was offered a job interstate. I sent my boyfriend a curt text telling him I need to talk to him and he sounded panicked. He said, “Are we okay?” That was unusual for him. He’d always been so confident.

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The second sign that something was up was when we found out a mutual friend was cheating on her husband. We were in the car driving to the city and I started ranting and raving about her unacceptable behaviour.

Normally he’d join me in my conversations about cheating being a deal breaker. Instead he defended her. I felt a chill sweep through me but I promptly changed the subject.

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A few years later, after we’d moved in together, I was with his son in a food court. We’d just seen a movie. His son started crying, saying that he’d overheard his mum and dad fighting. “What are they fighting about,” I asked, concerned for his wellbeing. He said, “I heard Mum tell Dad that she doesn’t want to sleep with him anymore.”

I felt like I’d been shot.

With shaky hands I called her and asked if it was true. What followed was one of the strangest conversations of my life. We’d never spoken before but she gently explained to me that they had been sleeping together and expressed sympathy for me.

I wasn’t able to confront my boyfriend until hours later after both of his children had fallen asleep. That’s when he collapsed on the street and vomited.

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I moved out. He begged and pleaded with me to give him a second chance. He tried to explain that he still has feelings for his ex and that it is complicated but ever since he met me he had been certain that I was his future and she was his past. I was confused. It’s not like he slept with a stranger. Was that better or worse?

Also, how could I look his son in the eye? I was humiliated.

And, if we did pursue a future together, how on earth would we navigate our relationship with her? Their children were still young and they would have to be in each other’s lives. They would always be family.

We did eventually reunite. It took almost a year for us to figure out a way to move forward. Previously I had been naive and trusting, not batting an eyelid when he had to sleep over at her house because she was on night shift or when he told me he’d have dinner there and then come home. I needed a clean break, two separate lives.

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She became resentful. His children became awkward around me. My boyfriend and I had trust issues for years, but somehow, we made it through.

Apparently it is quite common for ex partners to sleep with each other after breaking up. There’s something exciting about it, something familiar. It doesn’t lessen the hurt.

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What I learned about myself is that I’m not as black and white as I thought I was, that life is more complicated than it seems and that when you are in love, you’ll do anything to make it work.

I hope I made the right decision.