Charlie says he saw it on the way back from Sydney. Seems he felt he was made by Kate's Marshal, so he ducked into the lav and swallowed his bag of heroin, but just then, the plane hit massive turbulence. Charlie inadvertently choked. And in that moment, after everything went dark, he saw this beautiful blonde woman and just knew they were together, like they've always been and always will be. Just as he was engulfed in love, he woke to find some sodding idiot (Hi, Jack, I still love you) asking him if he was okay. When Des mocks, "Well, that's just poetry, brother; you should write a song about that," Charlie rejects the poor, suicidal rock star mantle. "I've seen something real. I've seen the truth."
Sidebar: Now, I think (and I imagine many of you are with me) that Charlie's spectacularly beautiful blonde is some reality's Miss Claire Littleton
Shephard. EW.com's Doc Jensen thinks otherwise. He thinks Charlie's true love is Our Lady of the Poppies. Sure, Charlie's description, and his demeanor while he gave it, certainly don't make us forget the boy is a junkie, but I just don't think this show is that cynical. And I certainly don't think it would give us a Charlie that cynical, since our original Charlie willingly sacrificed himself for his loved ones. If Sideways Charlie's vision had anything to do with the Virgin Mary at all, wouldn't it be tied to the faith of original recipe Charlie's youth? Remember, before Drive Shaft, that Charlie was a fairly devout young man. Still, I think it's some Claire (and where this narrative is concerned, I think it ought to be some Claire) who somehow managed to reach Charlie in this reality, just like original recipe Claire's vulnerability and sweet nature was somehow able to reach the first Charlie through his heroin haze -- long ago and far away, in season 1.