Why don't you ask her what would hurt her. I think you might be making assumptions there based on what you see and THINK you know. Talk to her about it. I think that perhaps you need to do a whole lot more real in depth communicating with her and create a rapport before moving forward... you really don't seem to know enough about poly to make a call on what would work for you yet. So I would suggest doing some more work on your self, on researching poly and on getting to know this woman more before deciding. There is no rush and it sounds like it isn't a good time for her right now anyway.
Agreeing about the therapist. She isn't your mother, she is your therapist. Her opinion is not the point, her supporting you on YOUR journey is. If she isn't doing that, then I would urge you to find someone who does... that is sounding a tad manipulative and could be creating co-dependence.
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