There are moments in a relationship when one can know with absolute certainty that life has inexplicably shifted. This may come without warning or it just might be preceded by a scenario steeped in that “too late to turn back now” futility. You generally have the presence of mind to think: “Ah, excuse me world, when did I step onto stage 23? I know I didn’t wake up in a sitcom or romantic comedy this morning.Yet, at this very moment, I know that I must be existing in lines born from the mind of screenwriter. People don’t really have these conversations, we just laugh at them in theatres. Right?” This happened to me the other night. It was strange because Sean and I don’t…