The real showdown of the 2016 presidential election has been happening online.

In the months leading up to America’s big day at the polls on Tuesday, political arguments were raging on Facebook. And they often result in the unkindest cut of all — unfriending. The biggest social network on the planet has said that the 2016 presidential election alone has generated over 5.3 billion posts, likes, comments and shares, with nearly 110 million Americans participating in the online debate between January and October this year. The most talked about topic worldwide on Facebook in 2016 via words and hashtags was the U.S. presidential election. But it left out one key metric: Facebook FB, -0.09% didn’t say how many people have been unfriended. (A spokesman for Facebook said it did not have data on unfriending.)

“ ‘One little click to unfriend someone can give you so much satisfaction before you even step inside the ballot box.’ ” — Christopher Shea, a clinical social worker

Election or no election, Facebook users can be annoying. But the stakes are high for social media aficionados at both ends of the political spectrum. “One little click to unfriend someone can give you so much satisfaction before you even step inside the ballot box,” says Christopher Shea, a New York City-based clinical social worker. “It gives you an opportunity to exercise your conviction.” Some 7% of voters report they either lost or ended a friendship because of this year’s presidential race, according to a recent poll of 700 voters with social media accounts carried out by Monmouth University in New Jersey. Democrats are more likely to hit the ‘unfriend’ button: 9% of supporters of the Democratic nominee Hillary Clinton have done it versus 6% of her Republican rival Donald Trump’s backers, and 3% of other voters. This is not unusual for election season: 7% of voters say they have lost friendships over political campaigns in the past, but more than two-thirds of voters say that this year’s presidential race has brought out the worst in people and most disapprove of the campaign’s harsh rhetoric.

Listen to our new podcast:Money, Markets & More (or subscribe on iTunes): The latest episodes: “Is buying Ivanka Trump shoes a form of political endorsement?” and “East side versus west side: a division of wealth.”

The 2016 election season has certainly been more brutal and divisive than most in living memory with allegations of corruption and sexual assault dominating the news cycle even more than economic and policy issues, experts say. “It’s probably the most polarizing election that I can recall and it just keeps getting worse, and that bleeds out into our social relationships,” says Susan Krauss Whitbourne, a professor of psychology at the University of Massachusetts Amherst. She recommends people unfollow friends and relatives (where you hide a person’s news feed) before unfriending, especially if they’re your in-laws. “But when there’s no redeeming features left in that relationship and you feel it’s bad for your own mental health and getting you down,” she says. “That’s when you know it’s done.”

Don’t miss:This is one person you should never unfriend on Facebook

It’s not just a U.S. phenomenon. Facebook unfriending is a way of making a big statement across the world. “Politically motivated unfriending is a new kind of political gesture,” according to “I Don’t Like You Anymore,” a study published in the December 2015 Journal of Communication; two researchers from Tel Aviv University and Hebrew University of Jerusalem polled more than 1,000 Jewish-Israeli Facebook users. Some 16% of users unfriended or unfollowed a Facebook friend during the Israeli-Gaza conflict in 2014. “Unfriending was more prevalent among more ideologically extreme and more politically active Facebook users,” the study found. “Weak ties were most likely to be broken, and respondents mostly unfriended people because they took offense at what they had posted or disagreed with it.”

Read:5 reasons to flee the U.S. for Canada (that have nothing to do with a Trump win)

Some political supporters appear to manage a more diverse Facebook news feed: 47% of those who describe themselves as “consistently” conservative are likely to see political opinions that are mostly in line with their own view (versus 23% for all groups and 32% for those who are “consistently” liberal), according to a 2014 survey of more than 1,600 Facebook users carried out by the Pew Research Center, a nonprofit think tank in Washington, D.C. It may be no surprise, therefore, that liberals are more likely to drop a friend online or in real time over a political disagreement (24% of liberals versus 16% of conservatives). And liberals (44%) are also more likely to block people than conservatives (31%), a separate Pew survey of more than 2,150 Facebook users found.

“ ‘Unfriending has allowed people to become too insular, since it’s so easy to only read posts from like-minded individuals.’ ” — Joan O’Sullivan Jones, a homemaker.

Some cultural commentators lament the divisiveness on social media — and elsewhere — and also regard it as a sign of the growing intolerance for those who hold opposing political opinions. “Given it’s unlikely we really can change another’s point of view, I think it’s unfortunate if you unfriend someone because of this,” says Jonathan Wai, psychologist at Duke University in Durham, N.C. “It might be a sign that you may also not be open to considering different viewpoints broadly and that’s not good for your own personal growth. Maybe when you see something you find offensive, step away for bit and make the decision at a time when you are more calm and collected.”

“I don’t think social media has been particularly helpful in this election, says Joan O’Sullivan Jones, a homemaker and mother of two children, who splits her time between Williamstown, Mass. and New York. “There has been a lot of hyperbole and ad hominem attacks and very little thoughtful writing. I also think it has allowed people to become too insular in their views, since it’s so easy to block or unfriend people and only read posts from like-minded individuals.” Susan Krauss Whitbourne agrees. “We all have to live with each other after the election on Tuesday,” she says. “If you have friends from both sides of the political spectrum, well, kudos to you. Honestly, it’s great to have a range of people in your life. I wish more of us did. Being able to engage in political discourse without having to unfriend seems ideal.”