Dear Oona: Wow, that is great that your mom so very quickly had accepted your transition story and that she even gave you some suggestions too. Many time parents can be the most difficult challenge for a lot of transitioners.
I really would think that coming out to your therapist is NOT going to be much of a problem. Your case manager has already heard your transition plans and that doesn't appear to be a problem.
So.... all of that is wonderful and very good news.
I am so very happy for you. Please continue to keep us all updated regarding your transition progress as you press toward your goals.
Hugs and well wishes,
Danielle