Life & Style has exclusively learned that Selma Blair had been sober for three years before her meltdown on a June 20 flight from Cancún, Mexico — and only began drinking alcohol again on the Father’s Day trip.

Seated in first class with her ex-boyfriend Jason Bleick and their son Arthur, 4, the 44-year-old Legally Blonde star mixed what seemed to be medication and wine, completely losing control.

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The actress, who played Kris Jenner in the recent miniseries The People v. O.J. Simpson: American Crime Story, has since apologized for the outburst, calling it a “big mistake.” But the drama didn’t begin with that incident — and some believe it won’t end there, either.

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Selma has struggled with depression for years, Life & Style has learned. Once she returned to drinking during the Mexico trip, she lost all control.

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Selma made the decision to stop drinking because she's devoted to her child, but sadly, this was her undoing.

“Yes, she has problems,” the source reveals, “but that kid is her life.”

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