I think the most important thing is reminding yourself about "who" you are. Personally I think, that we are all souls - and not the physical body nor the ego -, which are experiencing different level of existence and what they are providing, on different dimensions / realms.
The soul itself is learning, experiencing which will always remain in itself in different ways, making it more powerful, wise. To experience, the soul have to incarnate and reach different dimensions and live in the way it can manifest there; such as we do right now on the material plane. This is a kind of dimension, and there are many other! Every dimension have it's "rules" and circumstances, what they can offer. How can we experience the physical realm? With physical senses, like scents, tastes, touches etc. The soul, as a manifested being on Earth will get everything which needed to experience the current realm. Same true with other dimensions!
This question is hard to explain, because to give a proper answer - and we can just guess or trying to use our knowledge we have, even if we are not sure if they are true or not, so it is up on our beliefs - , we should know which dimension we actually talking about. You can have different type of energy exchange on Astral realm (like in a form of having Astral Sex), but this is something what you can do without actually waiting for your physical body to become unusable.
The soul itself is already complete, and it won't die. Actually, souls itself are omnipotent by their own, but the chosen dimensions will make the manifestation into a different "existence", where it have to play based on different rules.