Genesis 22:2 He said, "Take your son, your only son Isaac, whom you love, and go to the land of Moriah, and offer him there as a burnt offering on one of the mountains of which I shall tell you."
When Abraham is told by YHVH to offer up his son, Issac, the word "love" is spoken for the first time in the Bible. The Hebrew word for love is "ahavah". This first mention of "ahavah", which is the very nature of God [1 John 4:8] occurs in direct connection with sacrifice, the sacrifice of a most precious and beloved son. Abraham could not have known at that time that his obedient offering would foreshadow and typify the love of our Heavenly Father who offered up Yeshua, His only begotten Son 2000 years ago.
Notice that in both cases love is directly connected to sacrifice -- and that the greatest love comes from God's sacrifice for our sin. The greatest love involves sacrifice; perfect love is costly.
There are times when loving someone is hard -- almost impossible it seems. Yet we have this precedent, Abraham, the Father of faith, and we have Yeshua the Messiah who consummated and perfected "ahavah" in the loving sacrifice of His own life.
So while it's easy to love when it feels good, loving when it doesn't -- expresses the love of God and His faithful servants. The Holy Spirit, our companion and comforter empowers us to love even when it carries a heavy cost.
Love, even at the most difficult times -- realizing that sacrificial love is the very nature of God!