One of the biggest surprises of the year has been the bedroom romance between the Kristen Stewart and Robert Pattinson. The on-again, off-again nature of their relationship came to a head in October 2016 when they had a blazing argument over the merits of veganism. The two haven’t been seen together since and at the end of October they both distanced themselves from the other.

But the damage had already been done and their passionate love story captivated the world. In the following months, dozens of memes and Instagram stories were dedicated to their romance. It wasn’t just Hollywood insiders who were in love with Stewart and Pattinson’s famous argument either – fans from all over the world were inspired to talk about love and veganism.

Their romance might have remained a secret if it weren’t for a certain coffee table book. In early December, the celebrity coffee table book The Royals: Life in the Kennedy Castle was released. The book was put together by famed photographer Chris Buck – and in it, we’re treated to an intimate look at the royal couple’s lives. It’s the ultimate wedding present for Stewart and Pattinson fans.

The two have been romantically linked since 2014, but only until recently have their friends and family members started seeing them together. In April 2016, Vanity Fair published a tell-all article in which Stewart’s sister, Jessie, claimed that Stewart had been secretly dating Pattinson since 2014. That same month, People magazine published an expose on the alleged relationship. It was around this time that Stewart began referring to Pattinson as her husband. She also wore an engagement ring from the actor.

All Ceases Between the Off-again, On-again Dating

The on-again, off-again nature of their relationship continued until October 2016 when they had a blazing argument over the merits of veganism. The two had been dating for four years, with Pattinson playing a pivotal role in her transition from fame to infamy. (He also stood by her in her time of need, which was demonstrated when he stood in for her father at the 2016 Golden Globes.)

During their argument, which was spurred on by Stewart’s decision to go vegan, they reportedly yelled at each other for hours. According to a source cited by E! News at the time, Stewart accused Pattinson of being uneducated and lacking in compassion. She then stormed out of the house.

Pattinson distanced himself from Stewart after the argument, but the two have remained close friends. Since the breakup, fans have wondered whether or not this was the end of their romance. But with every new development in their tumultuous story, their admirers have become even more eager to follow their every move. In early November, it was announced that Stewart had been working hard to rekindle her romance with Pattinson. Just three days later, a source told Entertainment Tonight that she had made an effort to patch things up with her estranged beau. That same day, Stewart attended a special screening of Pattinson’s latest movie, Snowpiercer with her mother and stepfather, Tom Hannigan and Jerry Hannigan. (Hannigan is also the father of Stewart’s half-brother, Benjamin.)

On Wednesday, 11/16, Stewart and Pattinson made their first public appearance together in four years. At a screening of the French film Rules Don’t Apply in Paris, the two were photographed cozying up together. Since their argument over veganism, Stewart has gone back to being the shy, quiet girl who often spends her time indoors. But even then, she wasn’t keeping her relationship with Pattinson a secret – her former nanny, Barbara Hutton, has reportedly been hired as a baby-sitter, further demonstrating her family’s support of the couple’s romance.

The Love Stories Inspire Fans Around the World

The celebrity gossip magazine press has dubbed 2016 the “Year of the Roommate.” In an effort to stay relevant, Hollywood celebrities have been speaking out about their friend (or, in some cases, romantic interest) living with them. Between stories about Khloe Kardashian, Kourtney Kardashian, and Gigi Hadid, to name just a few, there was certainly no shortage of celebrity roommate moments.

But beyond the celebrity bedrooms, there have also been numerous examples of fans committing to activism based on their love for a particular celebrity. Over the past year, we’ve seen fans stand up for causes they believe in, inspired by the celebrity couple’s romance.

The Vegan Challenge

For Stewart and Pattinson, the 2016 has been a rollercoaster. The couple fought regularly, with Stewart even accusing Pattinson of being abusive. The two were previously devoted to their dogs – but now that they’re together, they’ve found a cause that they’re passionate about. (The vegan cause particularly motivated Stewart, who has long been an advocate for animal rights and considers the couple’s vegan beliefs to be a sign of their “compassion.”)

The pair are now challenging themselves to go vegan for a month. The Vegan Challenge follows a familiar pattern – the celebrities will track their food intake and share their results with the world via Instagram. To date, they’ve completed the challenge four times and completed it with Jimmy Kimmel, Anne Hathaway, and Julianne Moore. (They’ve also done it for National Spelling Bee finalists, who must keep their diet secret because they’re supposed to be learning to spell.)

But it’s not just about losing weight. The aim of The Vegan Challenge is to raise awareness about the treatment of animals and the environment – and maybe even generate some interest in veganism. Since finishing the challenge, Stewart has been documenting her food intake on Instagram. On Thursday, she shared a photo of herself in a bikini with the hashtag #veganchallenge. She then followed up with a photo of her in a blue dress with the hashtag #weddingbells (the dress is by Vera Wang).

For her part, Pattinson has been busy promoting his new vegan restaurant, Estelle, an eatery located in London which serves everything from cupcakes to steaks. His Instagram is filled with pictures of himself sipping wine, which he often promotes at the nearby vineyard, Bottletree Wines. (The actor’s family owns the vineyard and he and Stewart are among its biggest fans.)

Pattinson also recently appeared in an Instagram video in which he discussed why he became vegan. He explained that he was inspired by several different factors, including his love for animals and the environment as well as the health benefits that come along with a vegan diet.

To date, the couple have completed the challenge four times and completed it with Jimmy Kimmel, Anne Hathaway, and Julianne Moore. (They’ve also done it for National Spelling Bee finalists, who must keep their diet secret because they’re supposed to be learning to spell.)

It’s Complicated

In addition to the off-again on-again nature of Stewart and Pattinson’s relationship, their friendship has been complicated by the fact that they both have children from previous relationships. It’s not just the celebrity gossip magazines that had to scramble to figure out who’s baby is whose – now that the world knows they’re a couple, people are curious about what kind of family mixup might have created Stewart and Pattinson’s offspring.

According to a source cited by People, Stewart and Pattinson’s friendship was strained when they learned that their children had been born during different time periods. The source explained that “[their children’s] births really bothered [them] because it interrupted their relationship.” They reportedly got into a fight and then stopped talking to each other for months.

But it wasn’t just about the children. The two were already drifting apart by this point – the source noted that they had been arguing over “little things” for years. In an effort to remain close, they would spend hours on the phone with each other, even when they were on vacation together. These days, they mostly stay in touch through their mutual fans.

Tangled Affairs

For years, Kristen Stewart had been the quiet, sweet girl next door. But as she began to find her voice, she revealed a side of herself that wasn’t seen before. Her rebellious side came to a head in September 2016 when she began posting racy Snapchat stories, leading to a 15-minute interview with TMZ in which she talked about her sex life, among other things. (Stewart has said that she didn’t think she would “ever be that open about [her] sexuality.”)