I think this is really a long shot because I have hardly any information, but maybe it’s familiar to someone?
It was in color, I’m pretty certain it was a movie but there’s a chance it could have been tv. I saw it a few years ago, and I don’t think it was very old at the time, but I might be wrong.
It was about a man and a woman who were a couple, and they experienced some kind of shift in reality, but I don’t remember what it was. I remember a scene of one or both of them in bed, either going to sleep or waking up, and something was different, or maybe they were anticipating it being different? It might have been that one of them disappeared from existence, or had never lived there, or something similar.
I think it may have taken place in a loft apartment.
While searching I’ve found some movies like this involving children disappearing, but I’m pretty certain something happened to half of the couple and not a child.
I know that’s not very much, sorry!