What causes a partner to cheat or become untrustworthy in other ways? Its a question researchers have been asking for decades and there is no set answer.

For example, you might be tempted to pawn off an infidelity as an indicator that a marriage is unhappy in the first place, but thats not necessarily true.

A study done by Rutgers University found that 56 percent of men who cheat and 34 percent of women say they are happy in their marriage, according to biological anthropologistHelen Fisher.

If you cant look for obvious clues such as an unhappy partner, how can you tell who is and who isnt worthy of your trust? Its a complex concept, but there are flags that indicate a problem exists.

Mind you, none of the following signs – all of them put together are definitive. The only sure sign is a confession or catching someone in an act of betrayal.Here are six things to keep in mind if you’re wondering.

It wasFreudwho pointed out that people tend to react to feelings of guilt by playing the blame game. Its a form of psychological projection. The goal is to project those feelings onto another person either unconsciously or as an evasion tactic. For example, if a partner suddenly gets paranoid about the other persons behaviors such as accusing them of sneaking around or excessive flirting, they might be trying to hide something.

Psychological projection is just one of a number of defense mechanisms that can mean something is up. Others include:

  • Denial– They flat out deny wrongdoing of any kind despite the clear evidence
  • Distortion– They twist the negative into a positive. I did that to protect you
  • Passive Aggression– Im not mad, lets not argue or whatever are passive-aggressive responses
  • Repression– Another Freud concept, this means trying to forget the things they do like flirt or lie. I dont remember doing that
  • Dissociation– Detachment from things that happen

All of these behaviors tend to rear their heads during a time of personal crisis like cheating on a partner or doing something else that breaks the trust in the relationship.

It is possible that a shift in sexual or physical behavior indicates untrustworthiness. Like projection, the need to cuddle or be more physically attentive when it is out of the norm can be a reaction to guilt or fear of exposure. To put it simply, if a partner starts to lay it on thick, you need to wonder why. What is the trigger for this sudden affection and gift-giving? If you are not doing anything different, what has changed?

Astudyconducted in 2007 by researchers at Berkley indicates that risk-taking behavior can be a sign of untrustworthiness. The study authors did a meta-analysis of trust antecedents and consequences and found a correlation between key behaviors like risk-taking and being worthy of trust. Basically, these researchers found there are certain traits that are good indicators of trustworthiness or, in this case, lack of it:

  • Risk-taking
  • Poor citizenship
  • Counterproductiveness

On the flip side, things like benevolence and integrity were positive signs.

When a person has a history of long-term relationships, both business and personal, it shows they have the ability to build trust. Its difficult to maintain a solid network of friends if you fail to deliver on promises or prove to be unstable in other ways. A study conducted by psychologists found that90 percentof people who believe they have a high level of morality will be dishonest to benefit themselves if they think they can get away with it. Over a long time, most of them will get caught at some point and that will show in their relationships or lack of them.

Your past relationship with this person counts, as well. Most people dont change over the long haul. If this person has done something in the past that makes them appear untrustworthy that matters, too. It is okay to forgive but thatsdoesnt mean you have to forget.

Your brain is better at judging people than you think. A 2014 study conducted byNew York University Department of Psychologyfound most people can gauge trustworthiness just by looking at someones face. The brain is able to pick up on social and physical clues that you dont necessarily recognize on a conscious level. If your gut tells you something is wrong, there probably is a reason.

Research shows that communication is the key to a strong relationship. Couples that effectively communicate develop more than just a marriage. They become friends and friendship builds trust. If one partner lacks the ability to talk it out, it makes them seem less trustworthy, especially about personal topics including children, friends and intimacy issues.

Twenty-five percentof couples experience infidelity from one or both partners. The ability to stay true to another person is really the heart of being trustworthy. Certain characteristics serve as flags that trust is a concern and recognizing them allows you to be more informed about the people you let into your life.

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