Aziraphale and Crowley don't communicate and it stems from their first meeting.
Let me explain.
Before the Beginning, Crowley is at his most honest and his most vulnerable. He tells Aziraphale so excitedly all about stars and how long it's hoping to take for them to form.
Aziraphale is also bluntly honest (a trait he never really loses but does learn to temper) in telling him about the 6K year timeframe.
Crowley then mentions creating a suggestion box and Aziraphale frets over him, concerned already, and we all know how much trouble Crowley got in for asking a few questions.
This sets the tone for everything after.
Crowley stops being honest - "I'm a demon. I lied." - which also means Crowley has been disparaging his own demonhood at least since Aziraphale looked at him askance on a wall and said, "You're a demon. That's what you do."
Aziraphale stops trusting him, but he never stops being polite. Crowley doesn't attack him, so he doesn't attack either. Not at the Ark, and not with Job's goats. Aziraphale is still vaguely seeing the angel he saw in the stars.
Crowley even gives him the permit so he can doublecheck that everything's above board, so to speak. Then we've got Crowley lying straight to Aziraphale's face about killing Job's children because Crowley still sees the angel in the stars who told him the world and his nebulae were going to prematurely end.
The angel who let kids die in the Flood.
Yes, the angel who shielded him on the wall and gave away a flaming sword, so there's some comfort that he won't instantly get smote - "smitten" 😇 - but still the angel who staunchly toes the party line.
After all's said and done and Aziraphale cries about being fallen - cries over being just what Crowley is, even after seeing Crowley circumvent Hell's rules - Crowley tells him he won't tell anyone.
Crowley is good at not telling anyone things, but so is Aziraphale.
Season 1, we get this. Crowley doesn't tell Aziraphale about the hellhound until the last minute. Aziraphale doesn't tell Crowley about finding Agnes's book. Aziraphale doesn't tell Crowley he's meeting with Nazis, and Crowley certainly never tells Aziraphale how he knows them.Â
Season 2, we get more.Â
Things Aziraphale doesn't tell Crowley:
• Deringer in a carved out book and gun license
• Drivers license he's had for 90 years - as long as Crowley's had the Bentley
• Why his French is so bad (not until he's asked a direct question)
• He knows Crowley likes to rescue him
Things Crowley doesn't tell Aziraphale:
• Beelzebub dragged him to Hell and made him an offer
• He'd never shot a gun before
I'm sure there are more things I'm forgetting, but those are some of the big ones.
More evidence of their continued lack of communication after the Apocanot is the apology dance. (Although I love it and do need to see Aziraphale do it too.)
Crowley is not wrong, and Aziraphale is not right. They are both both. But that never gets discussed, which is why Crowley never has to talk about being brought to Hell. He never talks about Aziraphale being threatened by Extreme Sanctions.
Aziraphale doesn't know why Crowley comes back, but he very likely assumes it's because Crowley wants to do the right thing after all. Aziraphale is still thinking about the angel Crowley was (season 1, "You were an angel once") and sees every single instance of good as PROOF that Crowley could/should/wants to be an angel again.
Additionally, some of the things they do say don't get heard. Aziraphale likes to tell someone he's doing good now that he's no longer reporting to Heaven. Crowley teases him for it twice, back to back. Tone of voice and "doing good again, angel?" after Maggie says something about the rent.
Aziraphale craves being told he's doing the right thing. Aziraphale has been pushed into a place where he won't get that from the place he always has because Heaven is out of reach. If he'd communicated this to Crowley, who is doing everything he can as always to keep him safe, that Crowley would keep teasing him? That Crowley wouldn't gesture to someone in need and say, "Right. Have fun, angel." Anthony J'acts-of-service Crowley would absolutely let Aziraphale have all the bouncy fun miracles in the world without shame.Â
Also, when they discuss how to make Nina and Maggie fall in love. Crowley's idea - canopy, rainstorm, vavoom - is absolutely informed by his own experiences, but he doesn't leave it at that. He says he "saw in a Richard Curtis film." He won't let that uncomfortable truth live in reality, pushing it off to humans and film. The realm of fiction, as Aziraphale immediately latches onto.
They don't talk about themselves. They don't talk about being an US. They said their side without getting into the nitty gritty of what that means to the point where neither knows where the line is.
Aziraphale says our car and when Crowley refuses because my car, Aziraphale also says they both get use out of the bookshop. Our car, our bookshop. It's a melding that Aziraphale assumes is perfectly natural, but Crowley hasn't seen it that way. They haven't talked about it.
And when they finally do, Aziraphale is running on the assumption that because Crowley does good and was happiest as an angel, looking over a colourful nebulae - so happy with it, he didn't want to lose it and ended up Falling for it - of course Crowley would want to go back. Of course Crowley would want to be in charge (second in command) since it means doing what they do on a larger scale.
Crowley, however, is still keen to keep going as they have been. Alcoholic breakfast at the Ritz, fixing up the bookshop like nothing happened, getting Muriel away so it can just be the two of them. Crowley is ready for the status quo. Although he does have new knowledge that the car and the bookshop are theirs, he and Aziraphale still carried the plants back to the Bentley.
They are still not talking.
And when they do, it's too little and it's too late. And they never ask each other why.
Next season, they need to learn how to ask why. And I have faith they will.