Not that this is horrific, but I’ve thought about mortality many times throughout my life. The first time I realized I was going to die was when my mom, looking at a kitten, remarked, “Animals are so lucky that they don’t think about dying.” My reply was, “What? I’m going to die?”
The second time I remember thinking about my mortality was when I was about 13 and realized that I’d not live long enough to read all the books in the local library. A few years later, I made my loved-ones promise that if I suddenly died when I was in the middle of a book, they must finish reading it to my corpse.*
A more recent memory of knowledge of my eventual demise was when I understood why I became melancholy in the spring, my favorite season. It was because I only had so many springs left in my life.
*this is no longer required