Do you think being in love makes a person slowly start to become lazy, too laid back and/or too relaxed as time goes by or, do you think it motivates them to be more productive in life?
I think this is more circumstantial than a generalization, and a lot depends on personality too. You can love someone for a long time and when they leave you, find yourself depressed, devastated, and unfruitful. On the other hand, how many songs, paintings, and movies have been inspired by the intoxication of love, which is euphoric in nature and a studied release of oxytocin in the brain. Everyone and every love story is different. Some will be overly stimulated and productive while others will find themselves in a state of despair.