There's this super ancient and presumably advanced race that thinks about things we wouldn't even understand.
They seed the galaxy with white eggs and black eggs. White eggs are basically angels like Adam, those from the tree of life. Black eggs, well, they're like Lilith. I'm not sure if the black egg which accidentally landed on Earth (which was supposed to be a white egg planet apparently) is in a unique situation where it split up into humanity or if ALL Black eggs have Lilith like creatures that will split into small, intelligent beings upon awakening.
Either way, we of the black egg gave up on powerful bodies and long lives in exchange for knowledge. But we began to isolate ourselves, shield our metaphorical hearts from harm to protect our fragile psyche. The absolute terror field, shielding us from each other so that we can't get hurt. Because apparently, sapience provides the potential for hatred, heartbreak, and all other sorts of nasty emotions that we don't like to deal with.
The idea as far as I can grasp it is that the angels are coming to reclaim earth as a white egg world for creatures born from life rather than knowledge. Whereas mixed in there somewhere is that conflict between the human ideologies. But what's important is that in the ending... of the movie that is... the anti-AT field is created from Eva01, the lance, Lilith, whatever, a lot of things happened at once! But it let everybody become one again so that nobody would be lonely. But those who can find their own "hearts" so to speak, and accept all the bad things that come with the ability to hurt and be hurt just so they can also experience joy, love, all that good stuff that comes with it, well they end up emerging from the sea of melted people (LCL) and will probably have a lot of cleaning up to do if they want the Earth to be livable again.