Are John Cena and Nikki Bella still together? Not quite. The pair have yet to rekindle their relationship after announcing their split just weeks before they were set to wed in Mexico. And ever since the Nikki took to Instagram on April 15 to break the news, things have definitely changed in both of their lives.

John, who turned 41 on April 24, celebrated his birthday without Nikki — something he hasn't done in years. He shared a video of himself lifting weights in the gym and captioned the footage, "41 years old. [350 pounds]. NEVER let age define effort. #EarnTheDay #NeverGiveUp #RAW."

Nikki didn't exactly celebrate the day with cake, either. She hit up a different gym with her sister, Brie Bella, and shared the photo on Instagram. While the twins made no mention of John's birthday on social media, Brie hasn't always kept her mouth shut when it came to Nikki's relationship.

While Brie may have been surprised by John and Nikki's split, she did always question John's motives and intentions with Nikki. During Season 2 of their Total Divas spin-off Total Bellas, Brie even called John out and Nikki and was caught in the middle of their fight.

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However, Brie, 34, took to Instagram on April 18 to clear up any rumors that she "wants to kill" John amid the breakup. She wrote, "I'll always love @johncena like a brother. He'll always be family. My heart is hurting for he and my sister."

So if everyone was so close, why did Nikki and John call it quits? Nikki and John's entire six-year relationship was documented on her hit E! reality TV series and from what fans could tell, they seemed to have a near-perfect, healthy, loving romance. But there were deep issues that plagued their relationship from the very beginning, stemming from a handful of things: the WWE pro wrestler's desire to never get remarried after his nasty divorce from his first wife, his desire to never have children, and his tendency to prioritize work above his family and personal life.

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Although John seemed to have changed his mind about marriage — he proposed to Nikki in the middle of the ring at Wrestlemania 33 — he still never changed his mind about children. That, paired with a sudden case of cold feet, is what ultimately ended their relationship.

"She never gave him an ultimatum," an insider told People, explaining that Nikki never pushed John to get married. "But as the day got closer, it was like he just went back to who he's always been — which is someone who puts himself first, always. He's an incredibly dedicated, driven, ambitious guy. And for the longest time he said he didn't think he had room in his life for a spouse or kids. It seems like in the end that was still the truth."

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Though it's unclear who broke up with who, fans seem to think that Nikki might have been the one to pull the plug on their relationship, and they think the reason is because of John's stance on having children. "Thank God! Nikki, you want AND [sic] deserve kids. Marrying John would have been a tragic mistake," one fan wrote on Instagram, while another commented, "You made a great couple, but you deserve to have a family. That's an incredibly selfish thing [John] did. If he loved you truly, he would want to have children together. He's about work….that's not what's important in life! His GREAT [sic] loss!!!!! Nikki, you will be an incredible mother! No doubt!"