Perception of Sameness

Because of the tendency to be egocentric in our thinking... It seems it is sometimes better to think that others are like ourselves, since there is a tendency to affirm our own way of being. Though sometimes I wonder about the genuine differences... When genuine differences are not acknowledged, Does that affect an individual's sense of identity? It seems identity works on two different levels... Who we associate with and have commonalities with... And ways in which we are different and unique from others.