I would suggest letting her read the letter. I wrote a rather lengthy letter in regards to that exact topic. It helped to have her know how I actually felt in those moments when they occurred instead of just my intellectual adult talking about them. We were able to work on things, normalize them, and it's a more open topic now which has decreased the stress/worry over it. I was a mess while she was reading it but once she was done and as we talked about it while she read it - it has been a great help in moving my therapy along. She needs to know how both the "inner emotional you" and the outer adult you feels about the topic, well in my case it was/is helpful for her to see and know "all sides" of me.

But it will help her to help you move forward and "change" as she will know more.