Have you realised yet that if you think four-dimensionally, nothing is impermanent? If you were to view the timeline as a plane from above, it would seem to exist as a permanent fixture, unchanging and eternal.
Even though there will be a point on that timeline when everything we know and love is gone, that brief snippet wherein humanity lived will remain as an immutable presence in the dimension where time has no meaning and all exists at once. The past, present and future all exist together (and simultaneously do not exist at all).
Every single event that has ever happened and will ever happen was a fated consequence of the first quantum moment, the formation of planets and galaxies and organisms simply the natural result of the subatomic particles doing what their properties dictate, even you thinking thoughts and reading this simply a product of the electrical impulses and cells that form us. In that faintest instant that this universe began, all of its time was prescribed from beginning to end, everything as a linear consequence of what came before.
It would be wrong to even say 'we are forever' because 'forever' would imply time meaning anything. We just - Are.