>>347395761
>You will spend countless billion of years alone
Subjective time is in subjective reality. One in the unconsciousness of anesthesia can subjectively experience a period of 12 hours passing in mere minutes.
The true reality would seem to be objective and spacetime is nonlinear from the frame of reference of objective reality. Once consciousness is bound to a physical body and can make observations from the frame of reference of one who possesses a physical body, subjective relative processes such as time and physics can be observed to move in a progressive 'forward' manner which is consistent with an increase in entropy. See the double slit experiment if you're curious about the question of how the conscious observer can change the results of an experiment and collapse the wave function. Reality is a state of superposition and it is difficult from our position of limited perspective in the cosmos to make many definitive claims.

What is certain is that the time before birth was impermanent, life is impermanent, and from those two facts we can extrapolate that the state of post-life too will be impermanent.