These Are the Top Signs of a Cheating Spouse—Notice Any of Them?

When most couples decide to commit, it's safe to assume that they're agreeing to a loving and successful partnership—but if only relationships were that easy. When Ashley Madison, a website that helps people cheat on their partners, got hacked a few years back, NPR reported that an astounding one in five Americans admitted to being unfaithful. If you've reached a point in your relationship when you're concerned about infidelity, then knowing the signs of a cheating partner may help you decide on the next steps to take in your relationship or on your own.

To be clear, the definition of cheating may vary from person to person—for instance, sending playful texts might be seen as completely harmless by some, while another might consider it as being unfaithful. That's why it's important to set boundaries early on in your relationship so that there are a clear set of rules and expectations.

It's also helpful to avoid jumping to conclusions. After all, many of these warning signs could indicate other serious concerns like depression. If your instincts are correct and your S.O. is cheating, experts recommend hearing their side of the story first, considering if they're remorseful of their actions, and then stepping back from the situation to determine if you want to mend your relationship or end it.

No, you might not be paranoid. Read on for seven ways to tell if your partner is cheating on you.

This may be the most obvious sign as a cheating spouse may be finding action elsewhere, but it's also worth noting that a loss of interest in sex could also be a signal of depression. New York–based couples mediator Laurie Puhn, JD, explains that stress over their career, finances, or a health issue could be a factor in their lack of libido, which is why it's important to have an open discussion about the issue. “Let [them] know that you noticed a difference. … See if this opens the door to a warm heartfelt conversation," she tells Reader's Digest.

If you met your partner after they broke off a committed relationship and they're exhibiting other suspicious signs of cheating, there's a chance your instincts could be right. "Second marriages are higher in divorce and adultery than first marriages," says marriage therapist Bonnie Eaker Weil, PhD.

When we suspect our partner is cheating, looking for clues in their incoming and outgoing call and text history is often the first thing we think of. Psychiatrist Scott Haltzman, MD, explains that if a partner readily offers up their phone for inspection after being accused of cheating, don't be so quick to write off your suspicions. "If [they] give you full access, it's a sign [they] may have a second phone," says Haltzman, author of The Secrets of Surviving Infidelity.

On the other hand, if your typically open-book partner suddenly stops sharing the code to their phone and other passwords and instead prefers to type them in for you, that may also be a sign to worry about infidelity. Puhn says that it's not uncommon for couples to need access to each other's devices, for example, when you need to find an e-receipt that was sent to their email account or the number for a family member.

"It's not that you need a list of [their] passwords, but should you ask for one—for a legitimate reason—[they] should give it to you," says Puhn, author of Fight Less, Love More.

People who have siblings are likely all too familiar with the classic "blame your sibling for something you did" trick. It turns out that this method of distraction is also among the top signs of a cheating partner. Marriage therapist Caroline Madden explains to Glamour that some cheaters use this tactic to put you on the defensive, reducing your chance to consider the opposite situation and making it seem as if they're the innocent party.

If your seemingly rocky relationship has suddenly smoothed out, the drastic change could be a red flag that your partner is meeting those needs elsewhere, says Madden. She explains that many of her clients find themselves surprised at their partner's infidelity when things seemed to be going especially well.

It's common for people and relationships to change over time. Case in point: Many smart and successful people swear by learning new things and picking up exciting hobbies as a way to boost creativity. But if your partner appears to be finding new interests—like getting into a new genre of music, traveling, or becoming enamored with a specific gym—out of the blue, it could be a warning sign that a secret S.O. is turning them onto new pastimes, according to relationship expert Amy Spencer. The author of Meeting Your Half-Orange suggests showing support for your partner and their newfound hobby and offer to join in. "If your partner insists on being vague, that could be a concern," she says.

Speaking of picking up new passions, if your partner is suddenly keen on grooming or getting in shape, it could be that they've made a midyear resolution to take better care of themselves—after all, why should the New Year be the only excuse to recommit to health? However, you might need to worry about your partner's commitment to your relationship if it seems like they're exhibiting signs of "mate poaching," according to a 2000 study by psychologists David P. Schmitt and David M. Buss. Similar to when single people are looking to attract new partners, it's not uncommon for the unfaithful to enhance their outer appearance with new workouts, switching to a new salon, or giving their wardrobe a major makeover.

Up next: How to determine if texting should be considered cheating.