OK, so I checked out this post to see what others had responded when I noticed that I too had misinterpreted "passing" and as I was reading the other responses, I noticed I was listening to a song, the chorus of which is "[you] only know you love her when you let her go" but the singer wasn't pronouncing the second "her" very well so all I heard, appropriately for this post was, "[you] only know you love her when you let it go".

Ain't that the truth!!!