To follow on to this, I just asked my partner who is a therapist and they had the same advice. They pointed out that a therapist often knows the resources in your area that will be able to help. For example, in my area, my partner was able to recommend several resources and therapy groups over animal companion loss. If your former therapist isn't able to help, they should be able to point you to resources that can help you.

I'm so terribly sorry for your loss. I mainly lurk around these parts but your post brought me to tears.