Dying

What is the definition of death? What do you consider to be truly dead? How do you know death?
I personally, have never felt death. I've died, sure. But I've never died forever. I've been shot, I've been slashed. I've been hung, I've fallen from heights humans shouldn't survive. And yet, as long as I come back each time, I will never know death.

I've never met another person with this condition in the thousand or so years I've been alive. Never told, only thought about it. Why me? Why am I the only one out of every human to ever live? Is permanent death even a concept to myself?

Well, there's not really a way to find out, is there?