I am so sorry you are in this situation. What a mess. That said, there is enough unhealthy relationship stuff going on here for five therapists. Do you realize how much time and energy you are spending on all this bulls***? It is dominating your life.

Life is short. Do what you need to do. But, personally, I do not see you finding any meaningful peace as long as these two are in your orbit. If I were you, I would focus on your dog. That dog will never manipulate you and will always love you for exactly who you are.