Katy Perry‘s popping bottles and poking fun at her own love life after finding out ex-boyfriend Josh Groban is officially off the market … jokingly mourning the guy she once called “The One That Got Away.”

The pop star hopped on TikTok Monday in a white bathrobe looking absolutely defeated … pouring herself a giant glass of bubbly and fake-crying after news broke that Groban got engaged to British actress Natalie McQueen.

To really twist the knife, Katy set the video to her 2011 hit “The One That Got Away” … the same song she later admitted was inspired by Groban after their brief 2009 romance.

Still, no hard feelings here … KP kept it classy-ish by captioning the post “congrats” alongside a champagne emoji for the newly engaged couple. Fans in the comments, meanwhile, were absolutely eating up the ex-girlfriend humor.

Katy first confirmed Josh was the muse behind the track during a 2017 livestream promoting her “Witness” album … a revelation that apparently blindsided Groban himself. He later joked on “Watch What Happens Live” that he nearly spit out his coffee hearing the news … before pointing out the lyrics didn’t exactly match his life.

Josh cracked, “I never owned a Mustang. I don’t have a tattoo. Are you sure that’s about me?”