1) The universe is expanding, and the expansion is accelerating because dark energy is overcoming the force of gravity.
2) Some think that at some point, gravity will overcome dark energy and the universe will shrink towards a "big crunch."
3) Looking at the expansion of the universe, going backward in time takes the universe to a singularity...
Why does the universe get that far, to a singularity? Why wouldn't it just shrink to the point dark energy overcame gravity again? the way that gravity will overcome dark energy in the big crunch scenario?
EDIT: And why wouldn't gravity and the other forces reach an equilibrium at some point?