It was a titanic struggle beyond the understanding of mere humans. A constant, endless collision of power against power. It could end, if only one power or the other was less than infinite, if only one will or the other could be worn down, or better yet, broken. It could never end, for the will of the Concept of Love was an unstoppable force, and the will of the Concept of Hope was an immovable object.
It could never end, for Madoka would always, always sacrifice herself for the world.
And Homura...Homura would always sacrifice the world for Madoka.