be ships that pass in the night

be (like) ˌships that ˌpass in the ˈnight

(informal) (of people) meet for a short time, by chance, and perhaps for the only time in your lives: We met on a course in Spain and had a wonderful time together. But we both knew that we were just ships that pass in the night.This is from a poem by Longfellow: ‘Ships that pass in the night, and speak each other in passing,...’.
See also: night, pass, ship, that