Boundaries with supporting someone with DID

Hi I am new to this forum.

For background for the last 2 years I have been supporting my best friend A in discovering she was abused as a child. She had repressed the memories which started coming out 2 years ago. I was there when the first trigger started and have been there through her starting to get flashes of memories to realising who the abuser was then the development of DID.

Her parts talk to me. I am the only person who the parts talk to apart from her therapist.

I have just gone with the flow with this. One part who is stuck in the trauma one of the littles who I will call B has formed an attachment to me. B sees me as a safe space and tells me not to go, and has told me that "he hurts me" and to "make it stop". B is stuck in the room where it happened and sees me as an angel sometimes but also sometimes see me as a real adult. B used to come out everytime I saw A but its not as much any more. I see A twice a week and B fronts less and less but she still comes out.

I have been seeing a counsellor who has told me I should put in boundaries regarding this and has basically said I should tell A that I love her and support her but I can't have B front. I get where the counsellor is coming from on one level. Seeing B I think is a bit triggering for me as she is stuck in the abuse room and the counsellor says I can't heal from what I have been told about the abuse (A/B has told me about the abuse memories) until B stops fronting.

I am worried about doing this. I think A will see this as a sign of rejection. I also don't think it's fair to say I don't want to see one of your parts anymore where I know that this can't necessarily be controlled. The counsellor thinks that I might be subconsciously being manipulated by B fronting.

I think this (saying I don't want B to front) will make A/ B feel unsafe and I am concerned about what this will do for A/B. I should note A has multiple parts but B is the one I interact with most.

I am also wondering whether this counsellor is right for me. She seems taken with the fact that we are "just friends" and asked in the first session if there was any attraction there (there isn't), and asked last session if our relationship is a like a couple relationship. It isn't, I know that, but the counsellor seems to think that because we are both single that there is some underlying romantic undercurrent which isn't helpful to me and detracts from what I'm trying to work on. A and I joke that when we see a new therapist that its a good sign when they don't ask if we are more than friends that the therapist takes what our friendship is based on what we tell them.

A and I know what our friendship is. She is like a sister to me. The counsellor said that she has been doing this a long time and she has never come across someone in my position. I think if I was her sister or it was romantic she wouldn't say that. I think one of the things she can't understand is that someone who is only a friend would do what I do.

I also feel like she is telling me what I need to do rather than guiding me into making my own choices. I don't feel like I can be completely open with her either as I feel judged about the level of support I provide A.

So two questions 1) how do I put in boundaries regarding B fronting to make both of us be safe?

2) how do I break things off with the counsellor? I have seen her for 3 sessions so far and whilst she has helped me recognise I need to put in some boundaries I don't think she is right for me. She works at a specialised centre and mentioned when we were talking about parts (not A's, mine) that if I want to do more about that, it's probably more general counselling which she can't do.