Nix ~ No offense or anything, but I really don't think you can make a song "your" song.....things like "our" song start to happen when you are on your first vacation together for example. You're in Paris, walking in Les Jardins du Champs de Mars and some accordion player passes by and starts to play some romantic song...first thing you do is getting the name of that song when you come back home.
And that peticulair song will always remind the two of you of the great summer night in Paris...
Oh well, nevermind the comment. Getting carried away here.