Empowerment to me and having power is the ability to control what I do, to make the choices I want, to speak up (as a previous poster said) whether it is in session or elsewhere. You still have all the power to send as many angry emails as you want, you just won't get a reply. But that's not the power you want.

What you are describing is the desire to control what another person does. Which we cannot, we which in my opinion have no right to do, whether we pay them in therapy or are married to them or are friends with them. It is his choice to read your emails, to respond to your emails, or to do anything else with or without discussion with you, especially since you are engaging outside of session.

I would center the problem at your desire to control him, especially outside of session. I think it's a normal and natural desire, perhaps one rooted deeply in infancy. In part it is the development of connection. When my son was a baby, he loved to discover things that would make me laugh or otherwise cause a "big" reaction, like tossing his food around the room. Someone posted a video of a mother and an infant "mirroring" I think, but that is also a demonstration of how a baby knows "if I do X, Mom will do Y", as opposed to being ignored or neglected. And we know how well it goes when parents neglect their kids, and of course an abusive response is part of this as well.

So we want people to respond to us, and there's some kind of mystical line between this normal desire (for reaction) for all relationships and the desire to control people. I lived through a childhood of being tightly controlled/intruded upon, so it was kind of natural for me to both have the desire to control others (which was mostly subconscious) and the desire to not control or be controlled, which could also go off the regular rails pretty easily.

So you can continue to send angry texts if you want, the power you no longer have is in his decision to not reply. He will give you a reaction in session if you want, like telling you he didn't even read the last one, but that's not the reaction you want. You are getting a reaction, though. You just can't control what reaction you get.

In my opinion starting back and exploring the desire to force him to react to your anger might be a useful therapy discussion. My guess is this is really multilayered and deep. Of course your current feelings are understandable but I don't think that's where the real work lies.