You aren't overreacting...I had a very similar dcg who was 4 years old behaving this way and worse! Parents just gave it into the behavior, they thought I was "expecting" too much...By Friday she was better, then a weekend with her parents giving in and Monday morning back to non-stop tantrums! I finally terminated and my days are so much better; im actually enjoying my time with the dck now. Only you really know how much you can take, how much more you have to give this family. My opinion is once the parents stop working with you, you are pretty close to the end. Good Luck