Something I meant to say and forgot is that it sounds like because of the complications with your email system your therapist ended up receiving your email more than once, and that she interpreted that as you expecting an immediate response. I think that is why she actually responded in such a testy tone! You could send a one line email explaining that you re-sent due to your email system being unreliable.

Given that it is so hard for you to open up I'm really sorry that the electronic difficulties (and her interpretation) resulted in such a discouraging response. Instead of sending another email it would be EVEN BETTER to go to your next appointment and discuss that experience, if possible? Also let her know that you find it easier to communicate in writing and see what can be done about this!