Is This a Real and Significant Societal Change?

In reading memoirs from times past or novels set in times past, I have often read of people referring to specific other(s) as, "my enemy." It just seemed a normal part of life at that time for any person to have a living personal enemy with whom to contend in some way or another. Yet, all through my life, I have never known or encountered any person to whom I would ever consider attaching the label, "my enemy." Is this a common experience today or do any among my readers have or have had personal enemies? Is not having to contend with a personal enemy a mark of a significant (and, to my mind, all to the good) change within our society?