Esther Perel has spent 45 years listening to cheaters. Here's the one thing they all have in common.

Finding a singular motivation behind cheating is a near impossible feat. 

As a Dating and Relationship Coach I've seen so many variations behind the reasons for infidelity. 

The motives range from unmet needs to impulsive choices, from opportunity to loneliness, and I've seen it all.

However, Esther Perel, psychotherapist and author of Mating in Captivity and A State of Affairs has done extensive research into the topic, and there's one prominent reason that keeps coming up. 

Watch: The number one cheating sign that everyone misses. Post continues after video.

What is it—you ask? 

It's 'deadness'.

What is deadness?

While the word may sound dramatic, it's actually the opposite. 

It quietly describes a state that creeps into many long-term relationships: a feeling of emotional numbness, disconnection, and personal erosion. As to which comes first, that's a chicken and egg type complexity.

Deadness is something that we can experience as an individual (as part of a couple) or feel applies to the dynamic of the connection. 

It's the internal monotony that may come from routine, emotional repression, lack of novelty, or the fading of desire. 

Whilst you still love your partner deeply you'll be equally plagued by feelings that something is missing. 

You might feel:

• More like friends than lovers

• Bored of your own life

• Exhausted by roles like "parent," "planner," or "peacemaker"

• Disconnected from intimacy, spontaneity, or erotic energy

What does deadness have to do with cheating?

Perel's research reveals that most people don't cheat because they want to hurt their partner or even because they've fallen for someone else. 

Often, they cheat because they want to feel alive again. 

From what I have seen infidelity most often comes down to selfishness, and by that I mean cheating is a by-product of a feeling of lack or insecurity within oneself. 

Cheating is an escapism; it can provide a type of "resurrection of the self", and also a deflection from the real issues at hand. 

Dodging infidelity.

The good news is that deadness doesn't mean your relationship needs a funeral held for it, but it does require conscious effort to avoid.

Here's how you can invest in your romantic relationships and breathe new life into them. 

1. Prioritize emotional and erotic aliveness.

Keep dating each other, and stay curious. 

Netflix & Chill every weekend gets boring and it will suffocate the elements of surprise, mystery and playfulness that are intrinsic to keeping erotic energy alive within a connection. 

Keep surprising each other, and don't wait for holidays or big occasions. Take responsibility for making small tweaks to routine, cuisines, date nights, outfits, and quality time. 

2. Love yourself, first.

If you feel like you've lost your creativity, your independence, or your individuality in the relationship, you need to fix that. 

Set boundaries. Spend time alone, without feeling guilty. Remember what makes you happy and consciously give yourself time to.

 Listen to this episode of Everyone Has An Ex. Post continue after podcast.

3. Talk about boredom and disconnection.

Avoidance feeds deadness. Intimacy grows when you can vulnerably share that you're feeling numb or stuck without assigning blame. 

These conversations can often actually open the door to reconnection.

When is deadness, just dead?

Not every relationship should be salvaged. 

If deadness isn't just a phase and is a reflection of deeper incompatibilities or unresolved resentment then it's time to bury it. 

If efforts to proactively work on deadness are met with indifference or if trust has repeatedly been broken without accountability and changed behaviour, then DNR. 

What else should we know?

Infidelity is many shades of grey and it does not necessarily have to lead to the end of a relationship.

 As Esther says so poignantly, "When we seek the gaze of another, it isn't always our partner we're turning away from, but the person we ourselves have become."

Deadness bookmarks an obstacle you either choose to accept or deflect; it doesn't mean the love is gone, it means aliveness needs to be reignited.

Featured image: Esther Perel.

Jess Matthews, colloquially known as 'The Boy Detox' is a Relationship and Dating Coach and founder of 'The Boy Detox Course', an immersive one-month disconnection from dating to find clarity. Follow her here.

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