One of the burning questions raised by Flashes Before Your Eyes is the identity of the elderly jeweler who lectured Desmond on the ways of fate. I actually think Des told us: she's a projection of his subconscious not unlike Dave.
I'm not referring to the Smokey manifestation of the latter -- I mean Hurley's imaginary friend from the mental hospital who wanted to eat tacos. Dave was the voice of Hurley's subconscious, including his appetites.
Notice how the jeweler played on all of Desmond's doubts about himself, echoing his subconscious feelings of unworthiness (e.g., "that's the only great thing you'll ever do"). Consider as well her claim that "we'll all die" if Des doesn't go to the Island. Mirrors his preoccupation of the past three years -- saving the world.
When Des accused her of being a figment of his subconscious, she didn't deny it, asking simply "Am I?" Shortly thereafter, she abruptly disappeared from his life -- just like Dave did from Hurley's. I'm guessing as well that Dave first appeared after Hurley's traumatic experience with the deck.
I'd say the implosion of Swan was a pretty traumatic event for Des...