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Hello and thank you for your question. I am very sorry that you are having these issues with your stepdaughter, I can understand how distressing this can be for you. Unfortunately if she is unwilling to take part in therapy, there is only a limited amount of options you can try. It does sound like she may have a Conduct Disorder given the behavior you described which is a purposeful pattern of behavior of breaking the rules and not following societal norms that are expected of her. I would recommend either she enter into a group therapy with other problematic adolescents because she may bond with the other group members and that can help her to break out of this behavior or at least try to work on herself more. The other option would be to try Wilderness Therapy, which is a specific type of therapy designed for children and adolescents that have Conduct Disorder and other behavioral problems. In this type of therapy she would be at a camp for around 8-12 weeks (some camps allow for school credit to be awarded too) where she will be obligated to work in groups with other teens that have a history of behavioral problems doing certain tasks in order to complete them and receive rewards/benefits. The reason this type of therapy works is because the only way to complete a task it to work together, so she will learn how to work with others, communicate, and learn empathy as well. Here is a good introductory article to help you understand how Wildernesss Therapy works
I believe this would be a good next step for her to help lessen her behavioral issues.