Katie has cheated, been cheated on, and been the other woman.

When it comes to cheating, Katie* has experienced the full spectrum. 

She has been a cheater. She has been cheated on. She has also been the other woman.

Katie had been married for two years when she started to feel like her relationship wasn't giving her what she needed.

"I felt like I was doing the lion's share of everything. He wasn't helping out in any way. He has children from previous relationships, and one of them ended up moving in with us full-time. I was doing all of the care for that child, as well as working and trying to upkeep the house," she tells Mamamia's news podcast The Quicky.

There had been countless discussions about her needs not being met in the marriage — either when it came to the mental load, household labour, emotional support or their sex life. So she decided to find a connection elsewhere.

"It wasn't just one person, it was a series of encounters."

Katie tells Mamamia that she didn't feel good about her infidelity, but justified it to herself. She figured the fact she was having casual encounters, rather than a relationship affair would result in less emotional damage if her husband were to find out. 

Eventually, the guilt became too much. Her mental health was waning too. She cracked.

Listen to the full story on The Quicky. Post continues after audio.

"I had a bit of a mental breakdown and he was with me in the hospital when I was admitted. I told him everything, and he was amazing to be honest. He was forgiving, and accepted that he hadn't really held up his end of the bargain as a husband, which I did not expect at all."

She adds: "He was willing to move forward, work with me and heal from that. But unfortunately, I think I was just too far gone by that point."

Months after telling her husband the truth, Katie decided the marriage had run its course. She asked him for a separation, and he agreed. 

After the marriage ended, Katie quickly moved on with a man she had been in a relationship with years prior. He was still married, and she became the other woman — falling for the "sob story" he was telling her.

"He would say, 'You were my one', 'I've regretted every minute since we broke up', 'You're my end goal' sort of bullsh*t. He also said the relationship was over with the woman he was with. He just said he was trying to get his ducks in a row."

Eventually, Katie said she'd had enough, feeling like she was being strung along by the man she was seeing. So she decided to end the affair and also made a very bold decision. She told the man's girlfriend that he had been unfaithful.

"I didn't tell her about me, I told her about the person that he had confided in me about, the woman who he'd been cheating with before me. She had a suspicion that he was having relations with this woman. She went back home, cleared out all of her stuff and went to her parents' place. She then sent him a text message saying, 'I know everything, I'm gone.'"

Katie convinced herself that she had done the right thing by telling her. But deep down, she knew her intentions hadn't been honourable.  

Katie and the man then became official and went public with their relationship. But the final leg of the cheating trifecta would soon catch up with her. Other people around Katie — including her boyfriend's own father — tried to warn her that he'd go back to his old cheating ways. 

"Shortly after the birth of my child I was at home with the baby, and I picked up my partner's iPad on the lounge. On the iPad I found some Facebook messages that he hadn't got around to deleting before he'd left to go to his other woman's place," Katie tells The Quicky.

It was a devastating realisation.

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Elisabeth Shaw is the CEO Relationships Australia NSW, as well as a practising clinical and counselling psychologist. 

"In a society where monogamy is seen to be the norm and the prize, generally you have promised that to your partner. Monogamy is based on trust and mutual commitment. So when you cheat, you know you have broken that boundary," Shaw tells The Quicky. 

Sexual Health Australia's data found that approximately 60 per cent of men and 45 per cent of women are willing to report that they've been unfaithful to their wedded partner.

The research also shows that 70 per cent of all marriages will experience an affair at some stage. 

While these statistics show men are more likely to cheat than women, scientists claim that women actually cheat on an equal level to men. Women are just better at hiding it and are less inclined to admit to it. 

The other question that so many ask themselves is whether the age-old saying 'Once a cheater, always a cheater' is true. Or can we change our unfaithful ways?

"The efforts you have to go to cheat require a great deal of gymnastics to get your head around it. There's a lot of justification. All the labour that goes into developing that narrative in your head can be used for the next situation. Unless you have spent some time reflecting, and really working out why you did that, it's probably at risk of lasting," Shaw notes.

The simple answer is not necessarily 'Once a cheater always a cheater', but there's a high probability.

So what does it take for a couple to overcome a cheating moment? Shaw says it takes quite a period of work.

"People generally start with a double down on monitoring and going into details. The wronged partner will often want all the details to really come to grips with what at that stage they perceive to be the competition," she explains.

"The mindset is 'Was there something wrong with me?' It's true enough that couples will look at their relationship and often find that closeness had slipped or intimacy had slipped. But the majority of couples can go through those minorly neglectful times without cheating. An affair is an active choice."

Today Katie feels like a different person to the one who cheated, and believes she's learned a lot from her experiences. 

"I have pretty much stayed single the entire time since and worked on myself and why I felt the need to do what I was doing," she says.

"Before that, I didn't think I felt secure in myself to be single, so I was looking for another relationship before leaving the previous one. It's taken three years of intense introspection to work out the root causes of why I cheated and not just jump to relationships."

Katie's identity is known to Mamamia. She has chosen to remain anonymous for privacy reasons. 

Feature Image: Getty.