Not getting yeur heart's desire means yeu've strived yeur entire life to reach a goal but never made it. It's painful and shows that things just turned out wrong, things were against yeu, or yeu just plain weren't good enough.
To GET yeur heart's desire... tends to mean yeu have little else left to achieve. Yeu can set a new goal, but it won't be the same. That one thing is special, sacred in its' own way, not in a religious sort of ideal though. It's like... once yeu have attained the single greatest accomplishment of yeur life... the rest is the anti-climax to the book; a dwindling, a fading, little left but to burn out and fade away.
The only time these tragedies are truly averted, are when yeu make yeur life's goals just before the end, when yeu still have time to savour the victory, yet not enough time for the realization to sink in that it's essentially over and there's nothing left.
Another awesome quote, which I think yeu may appreciate if yeu liked this one, is from Fleetwood Mac:
"There's two kinds of trouble in this world: Living, dying."
