If anything, an apology can be detrimental. Remorse? What good is remorse if you've done something that cannot be undone? What good is your sympathy; your clearing of conscience once the deeds are complete?

By apologizing, you give them conflict. You inherently demand, or at least ask for, forgiveness. And in doing so, you remove that other person's right to hate you. You remove that other person's knowledge that you will remain their enemy.

So in the end, for your own desire to show remorse, you would arrogantly tear down what they will have made into a coping mechanism?