The Cover: This relationship theory explains why millions of couples break up every year — and men are more likely to understand how it works

A relationship theory underlies millions of divorces every year – and men are probably more aware of this phenomenon than women.

The 'flip' is a term to describe a shift in attraction when the initial dopamine-fueled excitement of a relationship wanes and what happens in the future.

Either you stay in the relationship. ride and ride the inevitable waves, or you'll miss that first 'high' and abruptly leave to chase it with someone else.

Although the fascinating new term was coined by Dolly Alderton in her novel Good Material, the concept is not new. It's a jazzy way to summarize how men's and women's brain chemistry influences attraction over time.

'The 'flip' is a common culprit when it comes to relationship endings, and is closely linked to how men and women experience the stages of falling in love,' says relationship expert Louanne Ward told FEMAIL.

'In the early stages, our brains are buzzing with dopamine and serotonin, creating a laser focus on a partner and a desire to be with them. As the relationship progresses, energy dynamics change, causing changes in emotional priorities.”

The main players in this love game are dopamine, vasopressin, oxytocin and serotonin.

Men rely primarily on dopamine, a chemical that gives you feelings of pleasure, and vasopressin, a hormone that creates the desire to “bond” with a partner. The latter has been linked to behavior that leads to monogamous relationships.

Women rely more on dopamine and oxytocin, also known as the 'love hormone', because it promotes feelings of intimacy, trust and positivity.

“Around six months to four years of age, the dopamine wave that drives the excitement of the chase begins to influence the attraction phase,” Louanne said.

'As this dopamine party comes to an end, interest may subtly fade as we long for the exhilarating feelings of the first chase – entering the 'flip'.

The 'flip' is a term to describe a shift in attraction when the initial dopamine-fueled excitement of a relationship wanes and what happens in the future

“It appears that human nature inadvertently longs for the unattainable, similar to the constant free chemical high associated with dopamine and oxytocin.”

This search for long-lasting excitement can be compared to the allure of certain drugs, such as cocaine and MDMA, which activate these very chemicals, creating a parallel in which individuals seek an ever-elusive emotional peak.

“Whether you're the one chasing or being chased, blame our brain chemicals; they are the architects orchestrating this shift,” Louanne said.

“As the saying goes, 'You fall in love by chance, but you stay in love by choice.'

So the shift is essentially the result of our brain's complicated chemical dance as relationships evolve.

Men are more likely to be aware of this phenomenon because of the way they think.

“Once a man commits to a woman, which normally happens later than with a woman, his behavior changes because his testosterone drops,” Louanne said.

“Men are logical thinkers, they look for reasons, evidence and analysis as to why something happens, so it seems they are more aware because the change makes sense to them.”

So why does it lead to divorces?

Well, says Louanne, there are a few reasons.

First, the sudden change in emotional intensity can cause a feeling of disillusionment if you miss the initial thrill of the chase and mistake lust for love.

Second, if the relationship relies solely on the early intense feelings, the contrast after the shift can be discouraging and reveal the realness of what a relationship is and the person you choose.

Third, misinterpreting the natural decline of intense emotions as loss of interest can lead to insecurity and communication breakdowns.

When a relationship relies solely on early intense feelings, the contrast after the turn can be disheartening and reveal the realness of what a relationship is and the person you choose.

And finally, if the shift reveals underlying compatibility issues or unmet needs, it will lead to a reassessment of the viability of the relationship, potentially leading to a rift.

“You have to accept the change — the constant changes in the relationship or the transition from one relationship to the next,” Louanne said.

“It's emotionally immature to think that you can stay in a blissful state for the entire relationship once the honeymoon is over.” That is the moment when decisions are made.

“While it seems natural for one partner to appear more committed at various points, it is unrealistic to maintain a relationship in which one person consistently likes the other more.” There is no excitement and one or both parties will lose interest.”

A relationship can only survive if there is commitment to each other and to the relationship itself. Without this, you might find yourself simply switching from one relationship to another.

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