Ariana Grande is being blamed for Ethan Slater's breakup. Why do people target 'the other woman'?

Singer Ariana Grande has been called "not a girl's girl" by Ethan Slater's estranged wife, Lilly Jay, after Slater recently filed for divorce.

Grande has also been called a "side piece," and a "couple breaker," and she has been attacked for "shamelessly engaging in taking away a mother and her son's father away" by thousands of commentators on the "God Is a Woman" singer's Instagram account.

All this hate is expected in a society where "the other woman is often easiest to blame," according to a Saskatchewan-based sociologist.

"In western culture, even in celebrity culture, we still expect women to sexually police themselves more and to be the ones who are going to draw the line," said Sarah Knudson, an associate professor of sociology at the University of Saskatchewan.

Grande is far from the only female celebrity to be slammed for "ruining" a marriage or relationship. Celebrities like Angelina Jolie, Alicia Keys and Jennifer Lopez have also been criticized for similar situations.

Knudson explains that western culture expects men to always be tempted by other women and will try to engage with them romantically or sexually if they're interested — so it falls on the woman to keep him in check.

"People might look at somebody like Ariana Grande and say, 'Oh, she's somebody who's not going to control herself. She's not going to keep that boundary. She's going against what we're expecting,'" Knudson said.

According to Yahoo Entertainment, Grande has been "dating her 'Wicked' co-star in the wake of her split from husband Dalton Gomez." In mid-July, "Slater filed for divorce from his high school sweetheart wife, with whom he welcomed his first child last August."

"[Ariana's] the story, really. Not a girl's girl," Jay told Page Six last month. "My family is just collateral damage."

Knudson said it's an "icky position" to be the woman who gets cheated on because all sorts of insecurities will get triggered.

"(She'll wonder) whether (the other woman) was aggressively tempting from the outside or whether her partner was looking for an excuse to do it," she said.

The wife is also going to compare herself to the other woman.

"There's this weird issue that comes up where it's a woman kind of betraying another woman ... and you could look at this sisterhood and say ... 'Why would you do that to me? I wouldn't do it to you,'" said Knudson. "You've dishonoured this big code."

This doesn't mean that the spouse isn't hated on, but "the anger definitely seems to go towards the woman," Knudson added.

"I think it's a whole ganging up thing. ... Like your women, your friends are going to rally around you and see that the woman is probably the worst offender. They'll probably see your partner as having done something nasty too, but the woman on the outside is particularly the one you want to keep away."

Knudson says some therapists believe if someone cheats, it says more about who they are than it says about their relationship or who they cheat on.

"It shows that you weren't fulfilled or it shows that your expectations or your boundaries are different," she said.

But if somebody is cheated on, then they often tend to think it's about them.

"They don't think about it as being about the other people and the other people's values."

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