I think the questions in your email are very appropriate and deserve answers. Only thing is... and this is based on my own experience with a toxic therapist, I think there is a 99.9% chance that ex-t won't give satisfactory, honest answers. People like that won't get the harm they've caused, and sure won't take response for it or express genuine grief for the pain they've caused. So even if she responds to the email, what you get out of it may be more self-serving dishonesty that will prowling the pain and be another group of things that you'd want her to explain. What she did was not therapeutic in the first place. She's not going to figure out how to be what she isn't when she gets the email.