My Friend is Dying

How do you say good-bye to a friend that you work with? My relationship has always been one of his perceived "power" and my perceived "lesser-status". It is a relationship between a doctor and a nurse. We fought for over 17 1/2 years, but always maintained a sense of caring. I knew he was a jerk at times and he knew I was a shrew at times. But we always knew what it "was about" even when we fought with each other. I worked with him exclusively for 5 years as his case manager. And now it is coming to an end. He is dying. I can hardly stand to think about it. And I cannot stand to not think about it. This is the end and I am not ready. There are so many things I would like to tell him. All of them telling him what a good doc he was and how he saved so many lives. He was the best diagnostician I have ever seen in 32 years of nursing. I always told my family that if I was sick they had to call him in. Now he is dying at the age of 61. OMG.