14/08/2014 16:42 BST | Updated 20/05/2015 10:12 BST

How To Spot A Cheater: Three Classic Signs Of Infidelity

If you think you've never been cheated on you're wrong, according to one woman - and trust us, she should know.

Rebecca Jane, founder of The Real Lady Detective Agency, is adamant everyone will be betrayed by a partner at some point in there life, whether they know it or not.

So if you've an inkling he may be playing away, statistically, he is. Sorry. To mark the release of The Other Woman I sat down with head of the UK's leading female only private detective agency, Rebecca, and asked her how to spot a cheat.

the other woman

The A-typical cheater doesn't exist... Unfortunately for those looking to avoid players, there's no checklist to figure out his potential for infidelity. "Anyone and everyone could be a cheat," explains Rebecca.

"Even the most unlikely of people can end up cheating, given the situation," she continues. "I wouldn't be surprised by anything in this job anymore."

She makes sense. Although I hate to admit it, I've cheated on a guy before. When I was 17, young, foolish and drunk off WKD most Friday nights, I shacked up with my ex-boyfriend while still "seeing" a boy from the sixth form down the road. I broke up with both eventually and never came clean to either party. My bad.

Perhaps I've got it coming? "We'll all be cheated on," that's one thing Rebecca is deadly certain about. "Whether you know it or whether you don't a partner will be unfaithful," she says.

I assure her I've never been cheated on, to which she simply responds: "It may not happen for years to come, but who's to say it hasn't happened already?" Wow. Reality sucks. For all I know my ex and the boy from the sixth form down the road could've been playing me like I played them.

However, there are ways to spot a cheater... According to Rebecca, if - like me - you're expecting your comeuppance at some point in the future or actually suspect your other half playing away, you need to look out for the following:

1. Their timekeeping. It may seem obvious but the legitimacy of any sudden influx of business trips to Manchester is probably worth investigating. "Darl, I'm working late" may actually translate as: "I'm shagging your best friend's sister."

2. Their iPhone. No, don't go snooping through his messages, but make a mental note of how much time he spends checking his phone. If he's glued to it 24/7 you might want to check out why.

3. Their mood. If he's got a suckier attitude than usual or his mood is up and down and round the bend he could be hiding something.

But don't lose your head... After 15 minutes with Rebecca I'm completely paranoid, but she reassures me (slightly). "Six times out of 10 a partner is cheating, but it's not always the case. For example, I remember one woman checked in on her husband's whereabouts on iCloud and when he wasn't where he said he would be she jumped to conclusions and called us in. Turns out he was planning her a surprise birthday party."

So he could be cheating but he could also be planing an amazing event in your honour. Hmmm, right then.

The Other Woman, starring Cameron Diaz, Leslie Mann and Kate Upton is showing in cinemas across the UK now.

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