Hi! I believe I can be of help with this issue.
First, let me say that your daughter's friend is fortunate to have you and your daughter on her side. This is very unfortunate that the doctor is unwilling to maintain her patient confidentiality. In the US the doctor's actions to reveal what the patient says in confidence to anyone the patient does not give permission for would be both unethical AND illegal.
And this is actually the key to my answer to you. I don't know the privacy laws in Canada but I imagine they are similar. And an easy way to find out is to confer with your doctor and ask him/her whether she can expect more confidentiality from other doctors. If so, then that is the first step for her: to secure her own doctor and a psychologist or psychotherapist.
And this brings us to the specific case here. A book on anxiety is not a bad idea and it can be useful for her. But I am concerned by your statement that she self-harmed. That is not a typical behavior associated with anxiety disorders. It now brings other, more difficult problems to the table that must be examined and dealt with.
She needs to be evaluated and treated by a psychologist at this point as well as a psychiatrist. Why?
Because the self-cutting is pointing to some trauma based behavior on her part. And she needs to be evaluated for disorders dealing with that. So this is something you need to encourage for her. You need to be encouraging that she CAN feel better and whole. She can feel like a whole and healthy person. Encourage her to feel that this is possible. That she needs to take the steps to get there. And those steps begin by seeing a psychologist that she feels confidence in. Offer to help her interview psychologists so that she feels confident.
I wish you the very best!
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