Sorry, i don't know your full history with this T so maybe I am missing some important details, but that letter is condescending, paternalistic, shaming, childish, and ridiculous. It sounds like he is throwing a fit, because he does not have the equanimity and competence to handle the situation. He probably feels like a failure and so is lashing out in anger, dumping the blame on you.

I see absolutely no acknowledgement that he might have failed in any way. What an utter dickhead. There is no compassion, just a lot of overbearing and authoritarian shouting and barking of orders.

So so many Ts fail to see that the very setup of therapy, and their own behavior, provokes in some clients intense neediness, and addictive clinging, to such an extent that the client simply cannot cope and might even be caught in traumatic flashbacks or abandonment panic. And when this happens and the T cannot handle it, they act like the client is some sort of spoiled or naughty child and impose punitive and shaming boundaries. This idiot needs to read a book on attachment theory and PTSD. He outlines the very responses a client would have in this situation, and then fails to connect the dots.

And ending therapy without giving the client a chance to speak is not only unethical, it is insane and dangerous. Might as well take the client to the edge of a cliff and shove them off.