I believe most people just don't understand what a meaningful and mature relationship means when you speak of "loving" one another. God chose the "husband/wife" relationship in creation to show forth the very nature of love that mankind "needs".
God is love. However, we can't truly love in relationship until we've actually been loved. People go throughout their lives and never really understand this. I've come to realize what love is in my relationship to God. We must be taught to love through experience and often through our own failures. Our love must be contrasted against 'God's love'.
Our natural love is born out of desires and needs that God doesn't have Himself. Most people "love" out of necessity and self centered desires to control others.
Such never builds a mature and lasting relationship that is MEANINGFUL at every level. It is a incomplete love devoid of self sacrifice and empathy.
Completeness in love is found in the very Character of God. It is unchanging and inexhaustible.
Most people see the "love of Christ" as "Stockholm Syndrome". Especially "Calvinism".
This life is design to challenge our perspective and prove our love of what "sort" it is. This is why I often mention the teaching of the willing servant found written in the law of Moses in Exodus
Exo 21:2 If thou buy an Hebrew servant, six years he shall serve: and in the seventh he shall go out free for nothing.
Exo 21:3 If he came in by himself, he shall go out by himself: if he were married, then his wife shall go out with him.
Exo 21:4 If his master have given him a wife, and she have born him sons or daughters; the wife and her children shall be her master's, and he shall go out by himself.
Exo 21:5 And if the servant shall plainly say, I love my master, my wife, and my children; I will not go out free:
Exo 21:6 Then his master shall bring him unto the judges; he shall also bring him to the door, or unto the door post; and his master shall bore his ear through with an aul; and he shall serve him for ever.
Loving those that do not love you only starts a relationship, it can never complete it.