Jason Derulo and Jordin Sparks' break up may shock fans who were sure the couple was headed down the aisle - but those who have been closely watching Jason Derulo and Jordin Sparks' Instagram or Twitter may have known something was up when Jason celebrated his birthday on Sunday, with not a single mention from his usually very vocal girlfriend.

Jason Derulo celebrated his 25th birthday on Sunday, September 21. Jason and girlfriend Jordin Sparks were always very public with their love for each other on Instagram and Twitter. They posted the photos below for their three-year anniversary. But on Jason's birthday? Silence.

Sleuthing fans may have noticed the lack of a "happy birthday" from Jordin Sparks to her main squeeze on Twitter or Instagram all week. Looks like it might have been a sign of their impending break up. The last photo she posted of him was the one below.

Jordin Sparks and Jason Derulo's split was confirmed to E! News by multiple sources, and the publication was told that their breakup was mutual but they still care very deeply for each other and will remain in each other lives as friends.

Derulo first confirmed the romance in January 2012 but the pair was first romantically linked as early as September 2011.

This break up may come as a shock, especially after all the engagement talk and phrases like "the one" were being thrown around in recent months. It's likely fans were expecting the couple to get engaged at any moment, not to break up!

As we previously reported, Jason Derulo explained the meaning behind his song "Marry Me" in an interview with ABC's Nightline.

"That's the reason why I wrote the song in the first place," Derulo said, "because I wanted her to know that when the time is right then it will happen."

He also made it clear that he was definitely planning on getting engaged to Jordin, and was even thinking about his proposal.

"It will be the most amazing time," the "Wiggle" singer added. "When I do get down on one knee, it's going to be one of the most amazing experiences of my life, but when the time is right."

As we previously reported, Jason Derulo also said that he knew his girlfriend was "the One" when they first started in 2011.

"I knew that pretty early on. I felt that when I was in the hospital with my neck injury," Derulo said. According to E! News, Derulo has previously praised his girlfriend for being instrumental throughout his recovery after he broke his vertebrae in January 2012.

"I felt different...I felt like I needed her in my world."

We're wondering where it went wrong?