I love posting about Republican Kelly having her own evil arc and how that changes Jack. But!
There should have also been an arc about how Kelly sees Dean trying to kill her son...and she gets him...and she agrees. (She's already canonically done this before! She tried to kill herself to kill Jack when Dagon told her their real plans and expectations for Jack and how his powers might make him evil regardless...). And she gets it now too. The two heart characters with their heartbreak plastered on their faces while their soulless son watches and slowly realises in horror that maybe he should be dead. They're thinking about stopping an unstoppable force but he's thinking about his punishment and worth. (More sam and cas kinda issue ukwim. And Also the dean-kelly- thing of Don't Hurt People, Be Good).
This is also why Mary should have been alive, and thought about the Apocalypse World where she successfully saved her sons by killing them before they could be tortured into becoming vessels and starting the Apocalypse at all. (Hereditarynatural, my permanent agenda). And Dean and Sam know that too.
As for Cas, he's trying to put Jack in the Cage. Where Lucifer was kept. Because he sees too much of Lucifer snd also Godstiel in Jack at that moment. And he doesn't have any solutions.
And Sam is there....knowing the toll of a soulless existence. And he's trying to get Dean to stop because he doesn't want either of them dead. He wants Jack to go on a psychedelic trip. Right into psychosis. He's already there, he knows.
And then here comes God, asking for two sacrifices borne from love.
And then none of them give it. So he takes it. This time, he takes both Dean and Jack. As he originally wanted anyway. If Dean won't dance to his tunes, he's not worth playing with. He's just a broken, useless toy. So he throws them away. And he starts destroying every world now.