How is love symbolic in a novel?

Love is symbolic in a novel when it is an expression of another quality, emotion, or psychological condition. For instance, the protagonists may be in love with each other, but that love may be symbolic of hardships or obstructions to be overcome. Or it may be symbolic of futility or obsession in cases of unrequited love, of betrayal or misconception such as in "Romeo and Juliet", of irony in "The Gift of the Magi", of possibly revenge or jealousy as in "The Lady or the Tiger". Romantic love is rarely simple mutual adoration; the belief systems and concepts and the past lives of the characters will determine and color the emotionalism of their feelings for each other. And, of course, there are other types of love -- parental comes immediately to mind -- in which the parent may love the child but still abuse or betray him/her due to his/her own insecurities or madness. That sort of love might symbolize repression or confusion, even psychosis. The symbolism is the mechanism driving or inciting the love leading to the story's conclusion.