"nothing lasts forever"
what aziraphale thought he said: you are more important than my books
what crowley heard: our partnership had to end some day
I’m not even sure that’s what he heard. Because like, even if he didn’t, right. Even if they’re just talking about the bookshop. Aziraphale is still basically going ‘Yes, this thing we both love and depend on is nice, but we have to give up nice things sometimes, don’t we?’
Remember what Crowley said about that precious, peaceful, fragile existence [they’ve] carved out here. Aziraphale is saying that’s about to end. And I don’t think Crowley can handle that loss right now. The season starts with Aziraphale telling Crowley his beautiful celestial creation won’t last and ends with him saying their life on Earth won’t last. The first, he’s visibly upset and deflated. The second, he’s devastated. Things keep being taken away from him.
I think he knows Aziraphale isn’t ending their partnership. But what he IS ending is just as painful. Everything the bookshop symbolizes, their tentative freedom, their precious fragile peace, Aziraphale is ready to let that go. And Crowley isn’t. That’s why he puts on his glasses and walks away.
THIS. The problem here isn't a complete miscommunication-- Crowley knows what Aziraphale means. He just also knows that Heaven is incredibly toxic, and he can't let himself get sucked into that toxicity with Aziraphale, no matter how much he loves him. Especially not if it means sacrificing their own identities and lives and joys.
Aziraphale means well, but he is literally going back to an abuser, and doesn't seem to understand that that's what he's doing. He's asking Crowley to change a fundamental part of himself to go back to that WITH him, and he doesn't realise that's what he's asking! He has perfectly good intentions, but what he's asking of Crowley is terrible!
And Crowley is 100% making the right decision by refusing! I've seen some people trying to defend Aziraphale by claiming that they're equally in the wrong, but I don't personally think that's right. Is Crowley communicating as clearly as he should? No. But I'm not sure it would have changed Aziraphale's decision even if he had. Aziraphale is relapsing! It happens sometimes during recovery! And true love or no, you should never let yourself get dragged back into an unhealthy environment that hurts you, not even for a partner or family member. The best you can do is make it clear that you'll be waiting until they wake up again.
I think Crowley was right when he said "I think I understand a whole lot better than you do." Crowley learned a whole lot sooner that Heaven and Hell are equally awful and pointless. He knows the best thing to be is free, and true to yourself. Now he just has to wait and hope that Aziraphale will learn that lesson soon.
I think in an effort to defend Aziraphale people are trying to move his share of the blame onto other things; making Crowley more at fault than he is, or the coffee theory, etc. But sometimes people make mistakes! Especially recovering people! I think most of the breakup IS Aziraphale's fault, and I think that makes his character even more loveable and relatable and interesting. Not to mention human.