I get the impression from the OP that email is allowed, but they don't always reply to said email? If this is the case; my T (who usually always replies) has "ignored" responding to a heavy email before (twice actually) - once because she said she didn't know how to respond to it (it would have required that she lie to me) and then the other time because she felt that she couldn't right a response worthy enough to equate to the intensity of the message i'd sent and she needed to speak on it in person. Those are just two other reason you can add to the list of possibilities on why they choose not to always respond.