I am so sorry your little Chloe is feeling depressed.  I don't know as much on this subject as some of our expert breeders.  You may want to post this in the Breeders Talk section.  I would think that after such a traumatic experience she would naturally feel depressed and confused.  I hope you get some suggestions and that she's feeling better soon. 
 
 
Btw-Congratulations on your first yorkie and Welcome to YorkieTalk!