John Aiken reveals the three key signs of a cheating partner: 'You've got a problem'

We've all heard stories where a partner's cheating was discovered with seriously dramatic flair.

Perhaps it was a hotel key mistakenly left in a jacket pocket, a mysterious credit card charge, or the classic arriving home from work uncharacteristically early to discover two people in the bed scenario.

However, a lot of the time the evidence of a lover gone astray is far more subtle.

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To complicate matters further, the advent of social media and mobile phones has made it easier than ever for cheating partners to go about their business and then cover their tracks.

If you've been feeling suspicious of your partner, Married at First Sight relationship expert John Aiken says there are a handful of telltale behaviours that can point to infidelity.

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They just require a bit of careful observation on your part.

The first, Aiken says, is a noticeable change in your partner's behaviour.

"Are they now going to work and spending later nights there? Have they started to go to the gym?" he suggests.

"What about the way in which they're getting about with different circles of friends? Look out for their behaviour."

Watch the video at the top of the page to hear the two other changes Aiken says are telltale signs of a potential affair.