Yet somehow, Perry and Brand still have some unfinished business:
Despite the fact that their marriage was "dissolved" in February of 2012, Perry is reportedly still doing some legal wrangling in order to have the marriage declared "annulled."
It may seem like a moot point now, as the Brand-Perry divorce was finalized back in February of 2012, but sources say Katy is intent on getting married again, and she wants the new union to be recognized by her church.
Yes, it's easy to forget - what with all the girl-on-girl action and whip cream-spraying bras - but Katy was raised in a deeply religious household, and while she may have abandoned many of her parents' beliefs, she remains devout in some regards.
A source says of the annulment:
"She's trying to get Russell to agree, but so far he's not cooperating. They still don't speak. It's important to her parents that her the quickie marriage not count in the church and she doesn't understand why he can't do this for her parents."
The troubled Sons of Anarchy actor and Katy Perry got together in 2005 and broke up in 2006, before her singing career took off. Lewis died in 2012 in a fall from a roof, and reportedly inspired Katy's hit "The One That Got Away."
Russell Brand, whom Katy Perry was married to from 2010 until December 2011, is the only man she's tied the knot with. It was a coupling that seemed so crazy it just had to work ... until it didn't work, then it just seemed crazy.
The relationship everyone loved to hate produced some actual good times as well as bad during 18 months of makeups and breakups. At least Perry can reflect on happier times with his "Who You Love," featuring Katy, and her own song "It Takes Two," on which Mayer plays guitar.
Robert Pattinson has been linked to Katy Perry more times than we can count in the past year. Have they ever actually dated? Or hooked up? They've clearly hung out a bunch, but the hard evidence is elusive.