Someone does not deliver himself to the others as a whole in common situations of life and often never in his entire life.
Anybody represents a whole, at least because anybody bears on a body that has all limbs bound together.
However, the others could receive only discontinuous aspects, ready for being interpreted as positive and negative. Or, in a moral sense, they reveal themselves as good and bad at the same time. Because everything separated from a whole cannot resist to such a double interpretation. Firstly in the history of philosophy, Heraclitus made a great picture of the both sided and opposed nature of the things that compound the unitary whole of the world.
We do not see the negative side of the properties that compounds someone only as long we envisage him or her as a whole. Therefore, the love for a definite person may ignore all her negative properties, and positive properties are also overlooked when we hate someone.
We cannot establish if the lover or the hater wrongs in their partial reception of the other. Both sentiments acts in their own right, both are naturally orientated to the person in a manner that is commonly called blind. Their short time life is due to such partial reception, too. If the person loved or hated is not really a whole for the others, it is not to be found a firm basis of sentiments. It is required something as the ancient platonic idea of beauty, a more than human and a timeless whole.
Otherwise, in human matters, we have to substitute this whole with an approximation of the world possessed by other persons. In spite of an immense literature about human sentiments, this world frequently opens to others through an exposure of clear material and bodily signs.