These days it feels like infidelity is everywhere we look, from the bevy of Hollywood marriages falling victim to (at least) one unfaithful partner’s antics to matchmaking sites like Ashley Madison that profit from adultery – and coin questionable euphemisms like ‘married dating’.

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Then there’s that friend of a friend who cheated on her husband of 10 years with a work colleague for no apparent reason.

So what should you do if your worst fears are confirmed and you discover your partner has cheated – or perhaps is still cheating – on you?

Why we cheat

Such is the secret nature of extramarital affairs that we’ll probably never know the true figures, but some estimates suggest a whopping 70 per cent of all Australian marriages experience an affair.

According to family relationship educator Wendy Driscoll from Lifeworks Relationship Counselling and Education Services, affairs can be intentional or unintentional.

“With intentional affairs, it could be because of a sense of entitlement and beliefs like ‘it’s my right to do that’ or what people have learned in their family and grown up with,” Ms Driscoll says.

Unintentional affairs may arise out of general unhappiness or take the cheater completely by surprise.

“Some people are unhappy and start talking to others and sharing things they’re not sharing with their partner and a line starts to be crossed,” says Driscoll.

“People can also be very happy, get involved with another person and get really excited by the other person even though they haven’t thought about them before. In other words, people aren’t looking for it but it just happens – they could be chugging along with life and not necessarily unhappy.”

Counselling psychologist Elisabeth Shaw, a spokesperson for the Australian Psychological Society, agrees that there is no single explanation for why infidelity occurs, but she says research shows an increase in opportunistic infidelity.

“This happens when a relationship is by all accounts okay, but when one partner is at a work function or overseas, for example, they get caught up in something that’s indulgent and opportunistic,” says Shaw.

Stay or go? 

Are you invested in repairing the relationship? Is your partner really sorry for what has happened? Does your partner want to reconnect with you and give up the affair?

If the answer to these questions is yes, Driscoll says with the help of professional counselling it’s possible to reconcile and repair your relationship.

“We’d encourage you to get some extra support because there’s a big journey ahead to rebuild your relationship. Once trust has been violated it’s a long journey to rebuild it.”

But even if your first thought is to pack your bags and leave immediately, Shaw says people often find themselves surprised at what they are prepared to do to fight for their relationship.

“In happier times, people will say they would never stay in a relationship after a betrayal,” she says.

“But when it happens in reality, they instead have to consider the affair in light of the complexity of their lives: years together, love for their partner, ways the relationship still works, fear of loss and loneliness and consideration of children, among other things. These become important reasons to persist, even when in pain.”

Both experts agree that both partners share the task of repairing the relationship. “The general rule is the strayed partner has to be the one who is forgiving of the upset and inquisition that might come quite regularly when the hurt partner starts to get anxious about where they are and what they’re doing,” says Driscoll.

Conversely, Shaw says you also need to take responsibility for staying.

“Initially you might say you’ll stay if your partner jumps through a series of hoops. That’s perfectly understandable but ultimately it’s not about how many promises they can make or how many times they apologise but [repairing the relationship] comes about through an authentic understanding about why you got there in the first place.”

Make it better

It might be hard to believe after you’ve just found out about your partner’s infidelity, but Shaw says the work couples do in resolving the crisis can bring about real relationship improvements.

“Sometimes couples say that they have actually reconnected and sharpened their focus on the relationship, which wouldn’t have happened if they’d just stayed in their normal pattern of relating,” she says.