Go to your appointment and know that she is a trained professional and will only use what you have told her to help you.

I was just discussing the issue of using emailing, texting and other social media with therapy. We both agreed that there are some big disadvantages to using these and your situation is one where it backfires. Emailing you therapist things that you regret is a hard thing to recover from. Just know that she has probably heard it all before. She should be a safe person to share with.

Best wished tomorrow regarding your appointment.