Define forever. You're familiar with the analogy. If the time of all life on earth were represented by the length of a football field then hairless primates & humans have been around for the width of a blade of grass. Is your forever the time represented by the width of the blade of grass or by the football field, -- because that kind of time is on a planetary scale? Even a forever of a thousand years is instantaneous.
A life can be divided roughly into three ages. In our first age our childhood & our teens we look at the elderly and wonder what they did to get old. We assume we're going to live forever. If our second age our adulthood we're utterly absorbed by equipping ourselves with saleable skills & selling our time for the highest fee. Time is income. If we're lucky enough to make it to our third age we experience changes we can no longer control. We shrink in height. Our skin begins to bubble slowly. We repair more slowly. We realise all we have is time & our time is contracting. It's kinda exquisite. There isn't any fourth age.
So snap out of any concept of forever & sooner the better. When you see someone elderly realise you are looking at yourself. You are already living as if you are going to live forever. That's the point.
Do not act as if you have a thousand years to live.
-- Marcus Aurelius