Adam Levine & Blake Shelton's Bromance Bottoming Out: They're 'No Longer Close'

Say it ain't bro! After 16 seasons as colleagues and sparring BFFs on The Voice, and Blake Shelton are besties no more.

According to an insider, "There was a lot of talk between them about keeping in touch and hanging after Adam left the show in 2019," but amid "lingering tensions," neither has made an effort.

The insider explains the famed bromance started fraying in 2015 when Shelton, 44, hooked up with fellow coach Gwen Stefani: "Adam saw Blake getting wrapped up in Gwen's world and felt like the odd man out."

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By the time the Maroon 5 frontman, 41, left the show, "he simply wasn't having as much fun since he and Blake were no longer close." In fact, the insider adds that Levine "may not even be invited to Blake's wedding to Gwen. They seem to have looked at their friendship as a chapter in their lives, and now it's closed."

Though their friendship has fizzled, Shelton has his hands full these days with much bigger (and more important!) relationships. On October 27 — after five years of dating — Shelton and Stefani made a special announcement: the two are finally taking the next step.

And, according to an OK! source, they're not going to waste any time. "They're hoping to make it official early next year," an insider recently told OK!, adding that newly engaged Stefani, 51, and Shelton are planning to host the celebration on his Oklahoma ranch. "It's the place that best represents their love story, so it's a no-brainer."

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Given the ongoing coronavirus pandemic, our source said that Shelton and Stefani are looking towards an intimate and low-key wedding event — and will only invite a few dozen friends and family members.

"Gwen's sons Kingston, 14, Zuma, 12, and Apollo, 6 are going to walk her down the aisle," said the insider, adding that the boys' father, Gavin Rossdale, won't be invited to the big day. "The guest list may grow once they finalize the plans, but as of now, Gwen really wants to keep it small so everyone can enjoy themselves in a relaxed and romantic atmosphere."