Universal love is not a feeling so much as a commitment to work for the happiness of everyone. Universal love is like the Bodhisattva vow in Buddhism to work for the happiness of all beings.
Universal love recognizes that all of humanity is our family, but it also recognizes that there is sometimes cruelty and abuse in that family. Universal love does not mean ignoring cruelty, it means remembering that life is an interwoven whole.
True justice is not an absence of love. True justice is love that protects the weak from the mighty, the poor from the rich, and the oppressed from the privileged.
Love in the form of justice is not content with punishing those who have been cruel. We can all be unloving at times. As Gandhi said, the purpose of our struggle is not to eliminate an enemy but to illumine a principle. And as Dr. King said, our ultimate goal is never retribution and punishment but reconciliation and the establishment of what he called the beloved community.
Love as a feeling is very unstable and unpredictable. I doubt it is possible to always FEEL loving, but remembering the interwoven-ness of life gives us a powerful foundation for growing in love and a starting place to return to when we cannot feel love at all.