Hi, welcome! Folks around here consider this good news, after the initial big shock. One of the best things is, you have some information to make some decisions with. Another good thing is your child is still the same fun child you've had all along, and you seem to be doing a wonderful job with her.
Have you considered homeschooling in lieu of an expensive private school which might or might not offer the challenges your child will need? I myself don't homeschool, but leave it on the table as an option.

https://twitter.com/asimom, https://contributingfactor.wordpress.com