Raising a Child with Anxiety

They say that the definition of insanity is doing the same thing over and over and over again, while expecting a different result.
Sometimes I wonder what it means when you do the same thing every morning and always experience a different result.  That's what it's like parenting a child with Anxiety.
We never know what will set her off.  Some days are perfectly fine.  Other days?  Other days the wrong person woke her up.  Or I sat on her right side instead of her left.  Or...or we don't know because she can't talk.  She can only gasp for breathe between hysterical sobs and refuses to let me touch her.
She's doing well now.  "What are you doing differently?" her doctor asks.
"Nothing," I tell them, with a helpless shrug.
"There must be something," they tell me.  I think they're trying to be reassuring.  It isn't working.
The best I can tell, there is a cycle to anxiety.  I don't know how it works, exactly.  I'm not sure anyone does.  But as far as I understand she views the world in black and white, there's right and wrong.  She envisions a scenario, works out the kinks and plays it out.  She can adapt some days, when she feels quick on her feet.  And other days?
Other days, she hides under the pillows.
It's enough to drive a parent crazy.  And the worst part?  The worst part is asking for help.  Because there is still a stigma.  You must be doing something wrong.  We go over and over every moment of the day, every reaction, every pitfall.  We stress about every problem in our household.  (Although we realize there is nothing we can do to change the fact that she needs to share her room, or our financial standing, or choices we've made in the past, somehow it doesn't change the guilt) We talk about rewards and punishments, which only work when she decides they will and only bring us all to tears when she's too far gone to care.  (But consistency is key, they tell me.) 
On second thought, the worst part is the toll it takes on the family. Our other child can't help but feel the stress and act out.  I can recognize that she's acting out, but it's hard to convince her of that.
Raising a child with Anxiety isn't for the faint hearted.  It's not about reassurance or being patient.  It's about being ready for anything.  One day I say "Time for shoes," and she laughingly waves her be-shoed feet in the air, proud to have beat me to the punch.  Another day I say "Time for shoes," and she hides under a table.
But there are rewards too.  The snuggles and sweet whispers, the whispered stories, the innocent indignation.  She'll surprise us by washing her own dishes (but only her own, that's only fair) when the dishwasher goes out.  Or put hours of work into a surprise.  
We're proud of who she is, even when we're struggling to help her learn how to function in society.