What are they doing when they get right in each other’s face and rub their bills together?
I own two birds…neither parakeets…however my experience is that many birds do this kind of thing. I’d guess that its a kind of mutual preening similar to the way that some birds will preen each other’s feathers. Bill and feather maintenance are pretty high on the priority list for birds and based on what I’ve read I’d say that mutual preening would signify that you have a bonded pair.
Its not unusual for birds to bond together or to their human pet.
Also I think birds like the feel of having their beaks rubbed. My brown-head parrot likes a good scratching or sometimes enjoys running her beak over the textured fabric of our couch or ottoman
In other words…your birds kinda dig each other.