How To Tell if Someone Is Cheating: 10 Signs To Look Out For

Times have changed, and so have the telltale signs that your S.O. is being unfaithful.

Model holds phone and looks at another person with a suspicious gaze
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DEAR DR. JENN,

My boyfriend has been acting strange lately. Something just seems really off. We are talking less, having less sex, and there's just something different about him. I am worried that he is cheating. What are the signs? How would I know? —Suspicious

DEAR SUS,

I am a big believer in trusting your gut. If something feels off, you should listen to that. In the olden days, a cheating person had to worry about their lover calling their house on a family landline phone, or being caught at the neighborhood bar without their wedding ring. But times have changed, and the signs of cheating have changed, too.

Here are a few subtle hints that someone's stepping out.

1. They're MIA.

Your guy who is usually high contact and regularly available suddenly has periods of time where you can't find him or don't know what he's doing. When you ask, he is unable to provide information, seems flustered, or appears to be lying. A boyfriend who appears to be missing in action is very suspicious.

2. Their communication deviates from the norm.

You asked your normally detail-oriented boyfriend where he was last Saturday night and he responds "out with Jon." Or, you're a normally tightlipped guy who responds with more detail than a Bravo housewife describing her latest shopping trip. Basically, if they are acting the opposite of what you would expect, you may have a problem. In order to determine if someone is lying, you always want to look at what their normal behaviors are and spot deviations from those norms.

3. They are suddenly tracking your whereabouts.

If your partner is suddenly wanting to know exactly what time you were leaving for work, when you'll be home, and is asking for details about your schedule that usually do not interest him, that is a red flag. He may be tracking your whereabouts in order to make phone calls or visit with his lover.

4. You're being gaslit.

If you repeatedly have the experience of starting to question your reality based on feedback from your boyfriend, he may be gaslighting you. Often times when a cheater gaslights their partner they will accuse him or her of being paranoid, imagining things, being jealous, hysterical, or overly emotional. They will blatantly lie and do it in a way that makes you question your own reality.

5. They're protective of their phone and computer.

The number one giveaway is technology. A partner who is protective of their phone is a red flag, especially if this is a new behavior. If your boyfriend is on his phone a lot, and hiding it from you, you may have a problem. And if you think that would be super obvious, well the bad news is cheaters can suddenly become very tech-savvy. In this day and age, the technologically advanced cheater is likely to have apps that hide contact with their side piece. It's not just Ashley Madison you should be looking for. Some apps that range from seemingly benign to oh shit, are WhatsApp (encrypted messaging), Private Photo (an app that looks like a calculator icon but is really a secret file to hide sexy pics), Fox Private Message (an app that, upon shaking the phone, erases all previous text messages), and Nosy Trap (which takes a photo of you when you try to get into the cheater's phone). So, look for changing phone habits, and if you happen to see a flurry of new apps on his home screen, ask some questions.

6. Something is different about their car.

More mileage than expected can be a bad sign, as can significant changes in gas fill-ups, especially in new neighborhoods. A passenger seat that has been adjusted to a new setting can indicate that someone else has been riding shotgun in your place. And of course, like a bedroom, a car can be inhabited by belongings that don't belong, like hair ties, cosmetics, or even undies that aren't yours.

7. They recently had a makeover.

Many years ago, a girlfriend of mine started telling me about her husband's new look. He had lost weight, started going to the gym, changed his hairstyle, and upgraded his wardrobe. When she told me, my heart sank. My worst fears were realized when she uncovered that he had, in fact, been having an affair. Significant changes in appearance can be a leading indicator of an affair. New clothes and underwear are red flag city, especially when they represent a trend your partner has no history of caring about and you hadn't mentioned liking, either. If your partner, who used to love it when you did his laundry or shared laundry duties with you, suddenly wants to take over doing his own wash, you just may have a problem. Same thing with new bathing habits. The partner that suddenly is racing to the shower after getting home from work is concerning.

8. They have new interests and vocabulary.

When your partner suddenly has a totally different Spotify playlist of songs you've never even heard of, it should raise an eyebrow. Our tastes tend to be influenced by people, especially in romantic relationships when we spend a lot of time with them. The same goes for our vocabulary. We tend to absorb the phrases and expressions of those we spend a lot of time with. If you have noticed a lot of new vocabulary from your partner, you may want to ask about it. The same goes for interests. It is unusual for someone to pick up a new sport or hobby they've never even mentioned to their partner out of the blue. If your S.O. has suddenly taken up running, try to find out what inspired this sudden change.

9. You feel disconnected — and sex is more or less frequent.

When we are romantically involved with someone, they become our primary person. If you notice that your partner no longer tells you about their day, shares their struggles, or talks to you about things that are important to them, you have a problem. Connection is key in a relationship and not having that connection, or that focus going to someone else, is a problem. Changes in sexual frequency, technique, or intensity can also give you valuable information. It is not just having less sex, believe it or not, since sometimes cheaters actually initiate it more. Our libidos and sexual frequency fluctuate throughout the life cycle of a relationship, even years into marriage, but marked increases or decreases that you're not talking about can be a bad sign.

10. You've noticed money changes.

Sure there are the obvious credit card statements with jewelry or hotel rooms that you've never seen, but there are plenty of other signs to look for. Regular new cash withdrawals are a sign of a partner who does not want to leave a paper trail. New credit cards, junk mail, or bank statements from unfamiliar companies may be a sign that they've opened separate accounts. If your spouse is suddenly working longer hours but you're not seeing financial results or hearing about the big project that's keeping them late, that raises questions, too.

But is there a chance they aren't cheating?

Of course, the heavy caveat is that many of these behaviors are also a normal part of people adjusting their habits or interests, which can happen as we age, and throughout our lives, for myriad reasons. The number one red flag that someone's cheating on you? That's just your intuition that they are. So trust your gut. Even if they are not having an affair, you may be picking up on something else that's real and concerning. Take the time to get to the bottom of it without confronting or accusing them prematurely.

In Hump Day, award-winning psychotherapist and TV host Dr. Jenn Mann answers your sex and relationship questions — unjudged and unfiltered.

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