That is so unfair, I'm sorry that you worked so hard to get slapped in the face. Just reminde yourself you are doing an amazing job and she is no way nor has ever been you frriend! She is a user by the sounds of it! I hope for her sake she gets an honest daycare provider in the future who will tell he like it is. For you good luck and move on.

Experience is the name given to mistakes. Your only mistake was doing everything you could for a friend, that makes you a great person, so don't beat yourself up.