There are two explanations for this dream. One: Dogs are the representatives of friends in people's minds. Dog madness also proves that you have an argument with your real friends. Grandma's house is the harbor of your heart, perhaps the place where you were protected and relied on in your childhood, and subconsciously you will feel that it is a safe place. So in your dream, you will go back to your grandmother's house and subconsciously think you can feel safe there. In your dream, trying to defend your spiritual harbor means that your relationship with your friends is about to break down, and you don't want it to enter your heart.
Two: Grandparents are old, and you are very reluctant subconsciously, and you are afraid that you will lose their protection in the future. When you need to rely on them, think of them. Blue represents freedom and black represents responsibility. You feel that freedom has been lost, so when the dog dies, responsibility will always accompany you.
Summary: This dream is a symbol of my recent insecurity.