People are in all kinds of relationships, and couples make those relationships work for them in all sorts of ways.

If you’re in a long term, committed, monogamous relationship, though, one of your worst fears might be being blindsided by an affair.

This study says there are patterns that lead to just that, and by identifying them, you may be able to head the heartache off at the pass.

As a big picture, affairs usually happen after a gradual relationship decline. Afterward, the relationship rarely recovers, according to the study’s authors.

“Infidelity is largely believed to have damaging consequences for personal and relationship well-being. Yet the empirical literature remains inconclusive regarding whether infidelity leads to relationship problems, represents a mere symptom of troubled relationships, or both.”

That’s what the study hoped to determine, and after analyzing 947 people (609 who had an affair and 338 who were victims of one), they believe they have an answer.

The results showed that following an infidelity, people react as you would expect.

The perpetrators reported lower self-esteem, lower relationship satisfaction, and lower intimacy. The victims reported only lower self-esteem and more conflict.

The study found the dramatic changes to the relationship actually occurred before the infidelity, though, with almost all indicators of relationship well-being in a gradual decline.

Both parties reported more conflict and less satisfaction before an affair occurred.

The vast majority of relationships in the study did not recover from the infidelity, though that was less true when it was the woman in the relationship who was unfaithful.

Additionally, people involved in a relationship that experienced infidelity struggled to recover their mental well-being for years after the event.