Death of me

What is the concept of the "death of me"? If your body changes so that it produces the structure and functioning of a different person thus this other person personality, self reference, name, memories, etc, and does not think that it is you any longer in any way, is this the death of you? If then the structure and functioning becomes identical to the way it was at some point when your body produced you, would this be a restoration of you? If this process does not restore you to this body then who is this person that calls himself you, and has your personality, all of your memories, has no memory of ever being this previous person, nor even of not existing for a period of time?

This process could over and over again with one to any number of distinct different person being created by your body in between when a you are created. This will not be a replica of you because the same matter could be recycled over and over again.

If you say this restored version of you is not you then it appears that something has been lost in the process of change and restoration. The physical is still the same so is there something that is supernatuarl that is lost?