I lost a long time P/doc T a few years ago because he lost his license to practice. I reacted much like you with the unbelievable grief. I had to find a new p/doc T but it took me over a year. I had a cognitive T and she helped me to get through this even though it was outside the framework of what she usually does.

My new p/doc T was very helpful in this. I once asked him when I would stop crying about this and he told me you will when you have cried enough but he would be there the whole time for me.
As hard as it is, a new T will help you with this. I still cry sometimes. I was with him for 20 yrs. Sending you safe hugs. I am so sorry you have to go through this. The pain is deep and lasts a long time.