Lydia and Ryan both work at the same hotel.  He is one of the restaurant managers, and she is one of the major event planners.  They are both natural servants to others, and especially to each other.  Her family is from Panama, where the sand is black.  His family is from North Carolina, where the sand is bright white.  During their ceremony they both poured sand from their native land into the same jar.  It was a beautiful moment, a metaphor for their beautiful story.