According to psychologist Esther Perel, author of “The State of Affairs: Rethinking Infidelity”, men are often criticized for cheating but the number of unfaithful women have also increased by 40% since 1990.

“Women are just as guilty of cheating but unlike their male counterparts, they’re so good at maintaining a double-life that often times it’s almost impossible to tell an adulterous wife and a faithful one apart,” Perel said.

The following are common signs that a wife may be keeping secrets from her husband, men magazine Best Life said.

She does not want the husband to do the laundry
Few wives object to their husbands helping with the laundry unless they have something to hide. Such behavior is often linked to infidelity, as romantic dinner receipts or traces of unfamiliar perfume may still be on the clothes.

She avoids posting photos with the husband
Bethany Ricciardi, a relationship and intimacy expert, said that if a wife removes photos with her husband or avoids sharing family pictures on social media, she may no longer value the relationship and wants another person to feel comfortable.

She stays late at work often
If a wife often stays late at work, it could be an excuse to cover up an affair. Even if she is working overtime, she might be spending time with a colleague she feels close to.

She suddenly changes her passwords
Many couples share passwords to their personal accounts. But if a wife suddenly changes them without explanation, she may be hiding something, such as private messages with someone else.

A sudden password change or reluctance to let her husband access her phone could mean infidelity.

She pays more attention to her appearance
If a wife starts an intense workout routine or focuses on improving her looks without any special occasion coming up, she might be trying to impress someone other than her husband.

She stops sending affectionate messages
Justin Lavelle, chief communications director at background search website PeopleLooker.com, said, “If your wife’s messages have lost that loving touch, then her attention might be going toward someone else.”

Most women like to make their partners feel special. When conversations stop feeling like those from the early days of the relationship, it may indicate she has lost interest.

She accuses her husband of cheating
A wife who frequently suspects her husband of infidelity may be projecting her own behavior. “These accusations are often a sign of self-guilt, and it also will put the blame on you, causing you to be on the defense and distracted from their actions,” Ricciardi said.

She gives gifts without reason
Everyone enjoys receiving gifts but if a wife starts giving expensive presents for no special reason, she might be trying to ease her own guilt. Relationship expert Charlotte Rivers explained, “It’s commonly known that gift-giving is a way to butter someone up when you’re feeling guilty about something.”

She often says she is unhappy
If a woman frequently complains about being unhappy, it could be a warning sign. A survey by the American Opinion Research Center found that women who described their marriages as “not too happy” were nearly four times more likely to cheat than those who said they were “very happy.” Nearly half of the women polled also believed infidelity was acceptable if the marriage was unhappy.

She prefers going out alone
If a wife who once enjoyed shopping or going out with her husband now insists on going alone, it could be for suspicious reasons. Following her discreetly on these occasions may reveal whether she is being honest about her destination.