What is the meaning of “My cat was back and so was I”? Had the author gone anywhere? Why does he say that he is also back?

Here the author wants to point out that his ideology of life has gone a complete change. His schoolmates have helped him with their open hearts. They have extended invitations for their houses. Their genuine concern makes the author touch his heart so much that he breathes a sigh of relief. He feels that the things will be okay very soon.
After a month woman came with a cat. The narrator grabbed and hugged her. His friends were hugging the narrator. This overwhelming feelings of loss and tragedy seemed to diminish. He was deeply obliged to the stranger who had brought his cat. He could not help say that he was back to his original self. In reality he had gone nowhere but had become exhausted with life due to colossal lose. He felt that he had returned to his original self like the cat who came to his house.

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