After a betrayal, the relationship is only worth working on if the person who caused the harm shows they're willing to learn and grow, says sex therapist Jo Robertson.
"A red flag will look like somebody's minimising what they did or minimising your feelings … A green flag is somebody who says 'Tell me what the boundaries are in this relationship now and I'll hold to those'," she tells Kathryn Ryan.
Many people associate infidelity with a sexual affair but betrayal can be any outside relationship your partner would not consent to, Robertson says.
"There's no hierarchy of betrayal … If it's a very, what the world might call, 'minor offense', you might feel just as bad or just as broken, just as violated [as if] somebody went and had sex with multiple people."
A typical "emotional affair" involves a special relationship with a workmate, Robertson says, spending one-on-one time with a coworker and divulging sensitive personal information about their relationship.
"There might be a little bit of touching … hand-holding, hugging, etc. And there's usually an element of secret-keeping, where they hide their phone away, or they don't look let you look at their phone or they delete text messages.
"For me, that signals 'Okay, no, you're actually holding something back here because … there's an element of flirting, there's an element of attraction and excitement [and an element of] emotional investment that a partner might feel goes beyond what's okay for a friendship."
Some people, when discovering an emotional affair like this, quickly decide "this is the end, I'm out, it's finished", she says, but that's not the most common response.
"It's so easy for people to look in from the outside and go 'Oh, you know, if they cheated I would leave'. And then once they're in that spot, they go 'This is way more nuanced than I thought it was'.
"There's usually going to be enough layers in the relationship already for you to give something a go. And the layers can be anything … we're really great friends, we have a lot of fun together, we have overlapping families and communities, we have all this property, we have all this business, we have all these children…"
Robertson doesn't recommend every couple work on their relationship after a betrayal but says people often decide it's worth trying.
"The question I always pose is 'Is there enough here for us to just experiment with reconciliation?"
The answer, she says, will be revealed by a "wait-and-see" process of conversations over a period of time.
So how does a person who's been betrayed decide whether to try and stay in their relationship?
In the beginning, staying for the children is usually a strong motivator to stay in a relationship, she says, but it can't be your "forever" reason.
Ask instead if the person who has betrayed the relationship is committed to change and growth, which can be evidenced via a higher number of "green flags" than "red flags".
"A red flag will look like somebody's minimising what they did or minimising your feelings … A green flag is somebody who says 'Tell me what the boundaries are in this relationship now and I'll hold to those.
"When I'm working with [a person who's giving red flags] I'll go 'hey, this sounds like you're really trying to make excuses for your behavior. And that signals to me that you might end up doing this again, because if you think this is a small deal, then you're vulnerable to this happening again."
People describe emotional betrayal as akin to experiencing the "death" of the person they thought they knew, Robertson says. But while it's true that "part one" of the relationship has finished and things will now be different, the next phase could actually be better.
"You might have a deeper, stronger connection, going forward, if you both do the work. But yeah, your relationship will always have that scar, if you will. It won't be a bleeding wound but the scar doesn't go away."
Expecting not to be betrayed is not a massive expectation, she says, and gaslighting is never okay.
"Anyone who makes you feel like you're crazy for being hurt or having boundaries is not a changed person and they are likely to do it again".
Infidelity is very rarely about sex itself, Robertson says, and more often affairs act as a "bandaid" for people who aren't skilled at managing their emotions.
"People who don't know how to manage stress, they don't know how to manage rejection, they don't know how to manage their anxiety, they don't know how to manage the boredom or whatever it is… the feeling of abandonment.
"If you've done something that's been a transgression on your relationship, then it's really important you learn how to manage [your emotions] in the future or you are vulnerable to it happening again."
A more useful question to ask than 'how can I trust them again?' is do you see the other person working to change and rebuild trust, Robertson says.
"Somebody who's [evolving into] a different person … they're more likely to make healthy decisions, potentially, than the person who's never done that work at all and also hasn't had an affair. Because they've committed to being different to change into being a better version of themselves."
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