I've never sent an email, but I've said it out loud. It was hard to tell her and I think it made my tone harsh and made me sound angrier than I was.

I agree that the best thing for yourself would be to go back and face your T and work it out. It will be good for both of you. Show up to your session with an intention of open sharing if you can, so you can talk about what made you send the email and how you've been feeling about sending it.