The Netherlands had three civil wars between 'North' and 'South'.

The first lasted 80 years and is usually depicted as a war between NL and the Spanish Empire, which in reality it was for just a few years, until the country split into a Catholic and a protestant half. This was followed by a lifetime of civil war between the protestant and catholic half where neither side gained significant ground. There were two more wars associated with failed attempts to reunite the two halves.

The result is that to this day the Netherlands are divided over 3 countries. Peaceful and stable, but weak and without real control over their own fate. Added together, it would have been in the op 10 largest economies of the world, so sometimes one can't help wondering what things would have been like if the union had been successful. It's difficult to imagine why catholic vs protestant was once such a big deal, but we've grown apart too much now to go back. Is the split better? I don't have an answer to that.

There was a one sided population exchange in the 16th century. Protestants were deported from the southern half. They took their money, connections and wisdom with them. It was beneficial to the north, detrimental to the south, which stagnated for centuries.

It's such a long time ago, most people don't think of it as a civil war any more, but as a war between different countries. No one was punished for the atrocities, the concept of heretics having human rights was unknown in the 17th century. The worst perpetrator, the duke of Alba, who made today's ISIS look like a bunch of hippies in comparison, is respected as a national hero in Spain.

The narrative today is that both halves think they won their independence from the other half. I guess that's positive.

The country didn't get over it, the split is permanent. No one except for a hand full of right wing extremists would ever think of it otherwise.