It is not always easy to show kindness to others ... especially towards those who are different or disagree with you. Yep ... absolutely true.
GOD is our father who loves us and wants what is best for us. HE KNOWS that our natural inclinations are very often NOT in our best interests ... or the best interests of those around us ... but, this one IS a HARD ask.
First, it can be very hard to separate the person from that person's behavior ... they can be so intertwined as to be all but indistinguishable. So, "love the sinner, but hate the sin" can be a highly problematic exercise, even for the most well-intentioned person.
Second ... quite obviously ... our natural proclivity when confronted by mean-spiritedness directed toward us by another person is to immediately lash out in retaliation without any reflection on our part. This is a difficult trait to overcome on a regular basis.
Good thing Christ is around to save us from ourselves, eh?