I think that time will lose its sense of unidirectionality at some point

I actually have no idea how to conceptualize this. Every theory about the far future I’ve heard has assumed that time will move forwards, even if there’s hardly anything happening. Would a point where time changes flow back propagate to cause universe destruction before that happens? Would dark energy just rip everything apart? Is time driven by dark energy? Would everything just stop? Would some component of space become the new time? The Lorentz diagrams, they do nothing! Penrose can’t save me now!