I have emailed the one I see, usually as one of the things to stop spiralling out of control from frustration and anger after an appointment. She has never said not to. I usually put it as an attachment she can read or not and I usually say do not respond. I also quit by email but she does not take that seriously. I have told her not to call me or contact me also (in situations where it could be possible) - I like to set boundaries too and to make sure she would stay away if I told her to do so. If you want outside contact, that may be something to put on your checklist when therapist shopping.