Casey, 29, shared a picture of herself at her pal's nuptials on Friday (14 March) and looked stunning in a bright yellow dress, teamed with pillar box red nails and black bow fascinator.
The glamour model, who finished sixth on CBB, attended the wedding with her close girl friends at Stubton Hall in Newark, Nottinghamshire.
While at the do, she shared a selfie on Twitter, telling her followers: "Gotta love a wedding :) x."
Casey and her pals also got involved with a photo booth that had been set up for guests to enjoy - along with a box of props!
The star then posted a collection of the snaps online too, saying: "More wedding madness, so many giggles #wedding #photobooth #dressup #girls #laughter #fun."
No doubt her friend's wedding came as a welcome distraction for Casey, who has been hard at work since CBB finished.
Not only is Casey getting ready to launch her own range of leggings, she is also bringing out her own collection of bikinis for bigger busted women.
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