How do I go about politely quitting with these cirstances?

Hello. Im having a really hard time figuring out how to best handle this situation so i am hoping that someone can help me. I have worked at a in home daycare since Jan. this year. At first I love the job, mostly due to the fact that I adore children and was going to school to become a teacher so I thought it would be good experience for me. However, lately things have been awful, I have witnessed many things that my boss does that I am extremely uncomfortable with including what I think is neglect and abuse. Because I am so against her methods, I do not want to go back to work , and I even called the state hotline to discuss it to make sure I wasnt overreacting. They told me I was right and that this lady is going to be investigated and so will anyone who works there. This being said, I need to quit but dont know how. She knows Ive been stressed so do I just go off that or do I tell her that I reported her and can no longer work there and risk retaliation? I dont want an enemy.