Recommended answer:
There was a long-time teacher at a school who was very gruff when he spoke to me. At first, I went out of my way to get his approval. Then I realized that he was compounding the problem. So I observed how he interacted with other teachers and discovered I wasn't alone. He was gruff with most people. I quit trying to gain his approval and, in the process, found out had learned his behavior from a former principal he had had whom he admired.