The pair split during the last series of the ITV2 reality show this spring, after Argent's affair with law student Ebru Sanlee was exposed by a magazine.
Despite Bright's claims this month that they were "just friends", Argent last week declared on Twitter: "Very proud of my beautiful GIRLFRIEND @LydiaRoseBright...Were back together guys! (sic)"
Argent's online comment has since been supported by candid photos of the couple walking hand-in-hand along a Marbella poolside and kissing in a jacuzzi.
Another picture obtained by The Mail On Sunday shows Bright drawing a heart on the 22-year-old's chest in sunscreen as the two sunbathe.
Bright confessed during her split from Argent that she still considered him to be "the one".
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