A pesky threesome rumor and can't get Robin Thicke down! He's never looked happier!

Yesterday news broke that the reason behind Thicke's split with wife Paula Patton was because he was having a secret affair with the woman they were carrying on a consensual threesome relationship with. But despite the shocking reveal and Los Angeles' 90 degree weather -- the "Blurred Lines" singer appeared cool and calm (and oddly really giggly) in his leather jacket earlier today when he touched down at LAX. We guess if the whole world found out that we'd been giving it to two women on the reg -- we'd be pretty giggly too!

On Thursday, Star magazine reported that the duo had been involved with the massage therapist, whom the publication referred to as "Jasmine," for two years. Patton was all fine and dandy with the menage-a-trois until she found out that Thicke and Jasmine had been carrying on their romance without her.

"Paula felt betrayed and humiliated by both Robin and Jasmine," said an insider. "These were two people she thought she could trust the most, but in the end everything backfired on her."

The 37-year-old's smile says one thing about his demeanor -- but maybe the all-black look is more telling of his current state of mind?!

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