I saw a diamond commercial on T.V. (not Zales or DeBeers) of 2 seedlings/spores travelling through the air together, eventually passing by a couple walking on the beach (the woman seems to notice them) The only words I remember are: "What are you doing the rest of your life..." Does anyone know this song?

Not familiar with the commercial but those lyrics ARE the name of a song. Barbara Streisand, & a few others sang it.

Yes, That is Dusty Springfield. She also sings 'Son of Preachor man'