It looks like someone isn't too happy about Jordan Rodgers' newfound love with 'Bachelorette' star JoJo Fletcher.

Just weeks after the couple's engagement aired on ABC, Rodgers' ex-girlfriend, Brittany Farrar, has spoken out against the pair and accused Rodgers of cheating. This past week, she has taken to Instagram to rant about her former relationship with the 32-year-old, allegedly posting proof of his infidelity. 

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In one post, Farrar published a lengthy explanation about her decision to out Rodgers as a "prolific liar and cheater," saying she isn't looking for fame or money. "All I want is the same thing that anyone else who's been wronged would want: the chance to share the truth," she wrote. She also posted a video to her account showing receipts for flowers that Rodgers allegedly bought for another woman while the two were dating, according to Us Magazine. The video has since been deleted. 

But Rodgers' past isn't bringing the couple down — on Saturday, Fletcher and Rodgers pretty much fought fire with fire, posting their own photos on Instagram to prove that they're still going strong amid the cheating rumors.

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On Saturday, Fletcher posted a photo of Rodgers holding her hand while wearing her engagement ring. The best thing to hold onto in life is each other.... & tacos," the caption reads. Meanwhile, the former football player also took to his Instagram to post a smiling selfie with Fletcher. 

Someone should be documenting this for a "Bachelorette" spin-off — maybe we can call it "Let's Prove Who's Happier on Instagram."

Follow Chloe Tsang on Twitter @itschloet