Good story, but might be a rip off of a graphic novel
"Ces jours qui disparaissent" is a graphic novel by Timothé le Boucher, printed in 2017, that is one year before "Jonathan".
It tells the story of two personnalities sharing the same body.
They appear one day out of two.
They communicate through videos they record for each other
They have likewise roommate agreements (like "i'll do the laundry if you agree to do more physical exercise...")
They have very different personnalities
until one personnality is taking over...