There is a difference between a living being and a dead being, it is not just the physical form. It is something separate from the body and I believe it goes somewhere when the body dies. This is just something I “know”, deep inside, can’t really explain it. It just is for me.Okay, but the energy of your body DOES get transferred when you die in a very clear cut way. If you are cremated, the potential energy contained by your body turns into thermal energy as your body burns. Decomposition requires energy but also releases energy back into the soil, to organisms that feed on it, etc.
"Mental energy" (or, a soul) is a human construct and there is no proof that there is any sort of energy that is released out of the body when a person dies.
I have also had experiences I can’t explain like many others, and these seem to indicate ( to me) the souls of people go on.
Some people have musical or artistic gifts. Perhaps some have a sense of another realm?