since you are an adult, there is no reason she should be telling your parent. she may be going on the assumption that you are a danger to yourself, therefore she has to notify someone, but that is typically to do a legal hold on you. but different people may have their own understanding of this. as you live in your mothers home..and are you still on her insurance? she may feel your mother is responsible for you and your care, thus urging you to get further treatment.

I would definitely talk to her about this as you cant have an open and trusting relationship with her otherwise. ask her her reasoning for wanting to report to your mother. stress that your mother does not make decisions for you after hearing her out and how this threatens your relationship. confidentiality says she tells no one unless you have signed a release saying she can. the emergency contact is not that release. the hippa release allows her to do so.