I agree with your gut here.
It is totally against my personal code of ethics to advise or direct a client into actions such as this, as well as to declare that a clients marriage is over.
I may repeat what I hear you saying, or I may question your choices and delve deeper into motives but never would I instruct you to call or put your hands on a situation for another grown adult.
As a client in therapy myself, in the past, I've had to terminate therapy relationships, and try to do so without a resentment, remebering that therapists are also human, with flaws and issues.
you deserve a really clear eyed helper now!