Popa: My point is that listening to romantic songs does not help give more meaning to your relationship with Hashem, given that in reality you are really single. Marriage in real life can give a deeper dimension to your relationship with Hashem; but being single and listening to romantic songs is just self contradictory.
Shir Hashirim brings out the marriage relationship, since our personal relationship with Hashem [being single or married] is really in essence identical to a spiritual marriage relationship.