Just because a person loves deeply does not make them invulnerable to error. Love can lead us into situations that are precarious and painful.
Elihu, God's young right minded man in the oldest book of the Bible, said this to Job...
"Look at the heavens, and see; and behold the clouds, which are higher than you. If you have sinned, what do you accomplish against him? And if your transgressions are multiplied, what do you do to him? If you are righteous, what do you give to him? Or what does he receive from your hand? Your wickedness concerns a man like yourself, and your righteousness a son of man." - Job 35:5-8 ESV
Even in a modern translation this passage can be difficult to understand. But, It is basically saying that we don't know how to love even when we have the genuine desire to love because our thinking can be Earth bound and errors have piled up to a point where we are willing to compromise for expediency's sake and not even realize it. We plea bargain our love to move things along... God doesn't.
"For as the heavens are higher than the earth, so are my ways higher than your ways and my thoughts than your thoughts. For as the rain and the snow come down from heaven and do not return there but water the earth, making it bring forth and sprout, giving seed to the sower and bread to the eater," - Isaiah 55:9-10 ESV
"Do not be conformed to this world, but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect. For by the grace given to me I say to everyone among you not to think of himself more highly than he ought to think, but to think with sober judgment, each according to the measure of faith that God has assigned." - Romans 12:2-3 ESV
"Let this mind be in you, which was also in Christ Jesus:" - Philippians 2:5 KJV
"The natural person does not accept the things of the Spirit of God, for they are folly to him, and he is not able to understand them because they are spiritually discerned. The spiritual person judges all things, but is himself to be judged by no one. 'For who has understood the mind of the Lord so as to instruct him?' But we have the mind of Christ." - 1 Corinthians 2:14-16 ESV
Jesus' love was not watered down or compromised. The Pharisees saw people as sinners but Jesus saw people a precious but lost. He loved very aware that the people He loved many times didn't know how to think. That didn't make Him superior to those around Him. He became a servant and teacher in compassion.
I watched a young couple care for their small children at Christmas over the course of a few days. They did it so brilliantly. Even though those little ones often didn't yet know how to think about many things those parents served and led those children with such love even though it was obviously exhausting.
Jesus watched how His Father loved people and then He loved them. We watch how Jesus loves people and then through Him we see the Father's methods.
Our own sentimentality can do a great deal of damage. When we see sentimentality creeping in we don't have to harden our heart, which is a natural impulse to protect ourselves. Instead we can just 'repent' by turning to God and His thinking.
Sin doesn't crowd out God's thoughts causing Him to compromise. God is free to think in grace because transgressions have been paid for and blotted out by the blood of Jesus.
God's love is expensive. He pays a price beyond what something is perceived to be worth on Earth. He pays in time and energy and teaches us to think like He does... if we are available to it that is.