"Too good to last," is the weaker corollary of, "too good to be true." In structural terms, if something is unsustainable then at some point something has to give. You may be able to study or work all day and party all night once or twice, but if you keep it up something like your health, an important relationship, or a critical responsibility will fall apart.
This beat is the inevitable consequence of the Virgin's attempt to balance her Dependent World and her Secret World. The tensions that built during No Longer Fits Her World snap, catapulting her in to the very conflicts she worked so hard to avoid.
Kim Hudson*calls this phase, "Caught Shining:"
"[R]eality hits and the Virgin must face the fact that she cannot keep her two worlds separated anymore. The Secret World and the Dependent World collide and the feared consequences manifest. The Virgin often finds herself punished, shamed, or exiled. ... In Caught Shining the dream of the Virgin is no longer a secret. She is revealed to the world."The catalyst behind her revelation may simply be the consequence of the Virgin's growth: she may, as Hudson says, "... grow too big to be contained by the Secret World." Or the circumstances that created the space for her Secret World may change. Sometimes others act to expose her Secret World. Someone from her Dependent World may recognize her. Or a confidant may betray her.
Whatever the cause, the critical consequence of this phase is conflict. Because conflict is precisely what the Virgin has been trying to avoid, this point in the arc of the Virgin's Promise takes her into the nadir of the cycle. Analogous to The Ordeal in the Hero's Journey, it is the beginning of her darkest times.
The more cynical scribblers may say, "Been there, done that--if you're a writer, it's definitional."
It does seem that writers are peculiarly susceptible to self-doubt (though it may be that we suffer no more angst than is common to mortals, it's just that we're better at expressing it), but the emotional ordeal of this phase in the arc is deeper: it challenges everything you thought you were becoming--either directly or by alleging damage to your dependent world.
You may be accused of neglecting your family, your job, or your future. You may be charged with making the people you care about suffer for your vanity. Or you may simply run into the realization that you have nothing more to show for all your efforts than a drawer full of abandoned manuscripts and rejections.
It's a time of questions and no answers.**
* Kim Hudson, The Virgin's Promise
** This isn't a pleasant place to stop, but that's precisely the point.
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