And he fell even harder for his wife Acheron for being best girl in HI3

Maybe I'm dumb, but I think those are two different ways to see HI3rd's story.
One can see it as beautiful epos about Kiana's journey to the Moon, as Acheron's pov. Hard but beautiful journey. Story about warriors fighting for all that's beautiful in this world.
While the other, as Aventurine do, can see it as dramatic trace full of losses, pain and despair. Story of heroes and villains. Full of sacrifices for the sake of illusory hope for descendants. Still full of spoken descendants suffering. For the sake of victory against all odds.
The truth is... I think both ways are correct.