I learned early on that life can be cut short at any time. In my med school class alone, one classmate was killed by her husband, another died of cancer, and yet another is fighting cancer now, diagnosed with lymphoma around the same time she gave birth to her first child. Hopefully she will do well with her treatments. And the patients I see, some go from healthy to dead within days, or even weeks. One memorable patient was an elderly dentist who came to the hospital because people told him he looked "yellow." He was diagnosed with pancreatic cancer, and less than 2 days later, he was dead after he developed a GI bleed and aspirated. It was extremely quick, and if there was any consolation to his family, it was that he didn't have to go through the prolonged pain and suffering that most patients do. He was healthy for all but 2 days of his life. Not a bad way to live and die.
Then there are the dreams. I rarely remember my dreams after waking up, but there have been a few times in life where I'll be struck by a sense of deja vu and think, "I feel like I've been through this before." But I do remember my dreams about death, only because they were so vivid and disconcerting. There was one dream where I'm lying in bed dictating my will, and another where I'm looking down at my body, and I don't recognize myself because I'm so thin and emaciated from cancer. The latter dream left me shaken after I woke up, and it still scares me to think about it.
This is why I try to live in the moment. Why I have no trouble spoiling myself after a long day at work, or splurging on a new pair of shoes that I really don't need, or traveling long distances to visit my family and friends. I don't want to have too many regrets when I die, and when I die, I want to feel like I'd lived a life well lived.