I think Nina is a parallel to Aziraphale and Maggie is a parallel to Crowley. The whole season Maggie is much more forward in her affection to Nina and keeps actively going after her like Crowley does in the end for Aziraphale as well as just following him around the whole time. While Nina herself is preoccupied with her now ex girlfriend and can't quite let go even though it's obviously an unhealthy situation with the girlfriend being extremely demanding and controling. Just like Aziraphale is preoccupied with heaven and the metatron pushing him into a certain role. "They are toxic we don't need them."
And then of course this little dialogue "When I'm ready I hope she'll be there but there isn't any guarantee" "There is." "You're not helping, angel."
When Crowley and Aziraphale will inevitably reconcile and Aziraphale comes to terms with their misunderstanding he hopes that Crowley will still be there for him, waiting even if it's not certain. But of course he will be.









