The question is better phrased by asking what will be the practical consequences of treating an offense as legitimate and ceasing the offending action (and perhaps also apologizing) versus treating it as illegitimate and standing your ground (and perhaps even escalating). Clearly, this is a difficult question of great practical value in life, and like every such question, it's impossible to give a simple and universally applicable answer. (And of course, even if you know the answer in some concrete situation, you'll need extraordinary composure and self-control to apply it if it's contrary to your instinctive reaction.)