Dec. 31, 2009: One New Year's Eve, Justin makes his first move by serenading Selena during his performance of "One Less Lonely Girl" during Dick Clark's New Year's Rockin' Eve special. The following year, the two were photographed together on many occasions, but denied romance rumors.
Sept. 22, 2010: Selena appears on The Ellen DeGeneres Show and when asked about her relationship with Justin, she nervously denies dating him, telling DeGeneres, "He's little, he's like my little brother."
The following year, the talk show host jokingly reminded Selena about "lying" to her about dating Justin.
Feb. 26, 2011: Jelena finally make it official at the Vanity Fair Oscar party, making their red carpet debut. Selena stunned in a low-cut red maxi dress and Justin sported a black suit with a matching red handkerchief.
July -- Nov. 2011: The couple attend a handful of red carpets together, including the 2011 ESPY Awards, the MTV Video Music Awards and shared a kiss on the American Music Awards red carpet.
Feb. 14, 2012: Justin gives Selena a diamond-studded "J" ring for Valentine's Day. The "Come and Get It" singer posted a since-deleted Instagram pic of her holding hands with Justin and showing off her new bling, captioning the snap, "I’m finally home :)."
The gift sparked engagement rumors, which the couple shut down.
Nov. 2012: Jelena break up for the first time. According to reports, the singers found it difficult to maintain their relationship due to their busy schedules.
2013: Reports surface that Justin wants Selena back, following claims that he had reportedly been unfaithful.
In March, Selena joked that she made Justin cry during an appearance on Late Show With David Letterman. After Selena confirmed that she was single, Letterman joked that he made Justin cry the last time the singer visited the show.
"Well then that makes two of us," Gomez quipped.
April 2013: Justin posts and then deletes a picture of him and Selena cuddling. Fans quickly screenshot the snap and shared the pic across social media platforms. A couple of days later, Justin posted the infamous "back together" black-and-white pic of him shirtless and Selena hugging him from behind.
May 2013: Selena and Justin reunite at the 2013 Billboard Music Awards, giving birth to a now-famous GIF of Taylor Swift making a face at the former couple hugging backstage. The moment makes it clear that some of Selena's friends are not fans of her ex.
July 2013: Selena releases the song "Love Will Remember," later admitting that it was inspired by her relationship with Justin.
Oct. 2013: Justin drops his single "Heartbreaker," which included the lyrics, "I still believe in love/ I still believe in us."
Aug. 2014: Justin posts an Instagram pic showing himself cuddled up next to his on-again, off-again girlfriend, leading many to believe that Jelena is back on. They were then spotted vacationing in Canada together.
Aug. 2014: Justin is arrested on Aug. 29, 2014 when an accident involving an ATV and a mini-van turned into a physical altercation between the driver of the ATV and an occupant in the mini-van. In the police report, Jelena admit they're dating.
Oct. 1, 2014: Selena hints of trouble in their relationship with a tweet that read, "Sometimes we think we aren’t good enough. But then I realize when I think I'm alone I have God." She also unfollowed Justin on Instagram. This marked the second time the couple parted ways.
Sometimes we think we aren't good enough. But then I realize when I think I'm alone I have God.
2015: Their relationship is clearly over, for now. They each move on but continue to often talk about each other. In an interview with Complex, Justin explains his former relationship, saying, "It was a marriage kind of thing… we were so in love." Meanwhile, Gomez told Refinery29, "Of course I got my heart broken. Of course I was pissed about it."
June 2015: Justin debuts his single "Where R U Now" and fans were quick to notice that in the music video there is an image that reads, "Where R [U] Now, Selena?"
Nov. 21, 2015:
Selena and Justin are spotted together at The Montage Hotel in Beverly Hills. Guests at the hotel bar even got video footage of Justin as he serenaded Selena. That same month, Justin told ET what he thought about his ex's latest album.
"I've heard a couple songs," he said of Gomez’s Revival. "I think she's great, super talented."
Jan. 2016: This was not a great year for their relationship. Justin began dating multiple stars including Hailey Baldwin and Sofia Richie.
March 2016: Justin shares old pictures of him and Selena on Instagram, upsetting and getting fans riled up.
Aug. 2016: Justin and Selena appear to engage in an Instagram comment war over Richie being bullied by fans. "I'm gonna make my Instagram private if you guys don't stop the hate this is getting out of hand," the then 22-year-old singer captioned his photo. "If you guys are really fans you wouldn't be so mean to people that I like."
In screen grabs obtained by fans, Selena appears to have responded, "If you can’t handle the hate then stop posting pictures of your girlfriend lol - it should be special between you two only. Don’t be mad at your fans. They love you."
In other screen grabs, Bieber appears to have responded: "It's funny to see people that used me for attention and still trying to point the finger this way. Sad. All love. I'm not one for anyone receiving hate."
Oct. 22, 2017: The former couple hang out at Selena's home in Studio City, California, sparking rumors that they have reconciled. The Weeknd has been on tour this whole time. A source told ET that the meeting was strictly platonic and that the two were with a group of mutual friends from their church, and it isn't the first time the two have reconnected since their breakup.
Oct. 29, 2017: Jelena are spotted having breakfast together at JOi Cafe in Westlake Village, California. An eyewitness told ET that "they seemed friendly. There was no PDA."
Oct. 30 2017: News spreads that Selena Gomez and The Weeknd have broken up. While the "Starboy" singer was supportive and cared for Selena, during her kidney transplant she relied on her friends while he was on tour and "really tried to connect," even renting a temporary house together in New York.