I too would be interested in the details of the harm that you are referring too? How has the therapeutic relationship impinged upon your other relationships, and life in general?
I have old attachment injuries. Deep and crazy-making at times. My therapist has taken an approach that allows in between session contact, whenever I like, and she responds when she is able. That has been magic for me - done me the world of good to slowly, painstakingly, start believing on an instinctual level that someone is actually steadfastly emotionally available to me in an appropriate way. She is also seeing me for no fee at the moment. Words can't describe how much I appreciate this.
I think appropriate boundaries differ in each different client-therapist relationship. Is it worth considering that your anxiety around your boundaries may be a defense? Perhaps you can't quite believe yet that you have a relationship this precious, and so are looking for holes in it and 'proof' it is not what it seems?
Please do forgive me if I'm way off the mark - I'm in no way saying this is true for you and your situation, just playing devil's avocado