I feel a bit beat up. Need advice. Should I send the following email? Preface and long story inside.→[More:]

I was invited to have an artistic discussion on a continuing project that got picked up by a big festival. The people invited are the director and another collaborator whom I have had long and previous relationships with. The director, in particular I have known for 8 years. She tends to go through a lot of people, because she can be difficult to work with. (Her communication style is very roundabout, though she is intelligent and impassioned.) In any case, the artistic discussion was preceded by discussion of business items. I am represented by an agency and have made it clear previously that I will not engage in these discussions, certainly not those where both of the collaborators are involved, and yet the business manager still pursued it. The meeting did not end in a hostile way, but I did express my unhappiness in private to the director. She didn't recognize how put out I was by the discussion. It wasn't too tense. Anyway, I want to really nail home the fact that they put me in a difficult position. I will discuss this with my agency, but I also wanted to personally express it because I have known this person for so long, and would at least consider us to be friendly. So, should I send the following email, (and cc the business manager and my agent)?

I just want to express again that I felt extremely uncomfortable with our discussions with {other artist} and {business manager} and yourself prior to our {artistic} meeting. Unfortunately, regardless of intent, I felt ambushed and placed in a very difficult position. Not the best place to begin discussion of art, and I think, ultimately detrimental to our artistic discussion. I hope that now I have made it clear that all business discussions are to go through {my agency} and I trust that it will not happen again.
Regards,
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