It took my daughter and me a long time to begin building our online presence, and I was recently asked to make a portrait of a dog through our online shop. The owner of the dog supplied me with photographs and I made a drawing using them as my references. She claimed to have loved the drawing so much that she wanted me to proceed with the finished piece. I worked hard and long and when I finally sent her a picture of the finished piece, she refused the work and made some rather inexplicably scathing comments about it. Well, hurt feelings aside, I did not ask for any compensation for my time; I just kept the drawing. I have been using this drawing (NOT her photograph, name, or any other identifying information) in my online portfolios and she has asked me to remove it because it violated her copyrights to the photograph that I used to generate the drawing. Now I have received notice from Facebook that my picture has been blocked because of her allegations and I fear more retaliation elsewhere on my internet presence; she has already left defamatory comments on my Facebook page, which I’ve since blocked (but we all know she can find a way to return if she so chooses.) Can you please tell me if she has the right to revoke permission to use her photograph AFTER the work has been created? Don't I own the rights to my own drawing? And what can I do to stop her harassment and make sure this doesn't happen again?What is the name of your state (only U.S. law)?