Do I have any recourse if I am subject to verbal abuse, intimidation and punitive actions such as to put children in danger if I am a volunteer ?

I am a foster parent and I am constantly being harassed and screamed at by the case worker. She will never return my calls if I need something for the children. I have complained to numerous people numerous times that she cancels visits with the parents but she does not let me know that the visits are cancelled. She attempts to assign me work with unrealistic and unneccessary deadlines and then screams at me if I can't comply. I have had to speak to her about driving with the girls on the phone. I have spoken to her supervisor...who also yells first listens second... and she has told me the behaviour will stop and it never changes. Christmas eve the girls were supposed to be driven to see their mom and get presents. The caseworker made it a point to tell mom and girls she would drive and give them presents when she really had vacation scheduled. Not only am I tired of the abuse it impacts my ability the effectively care for the children.