You never apologize. There is never any reason to. If you've done something, it's your own choice to do so. Take action with certainty knowing that you are following your own vision. Don't be guilted by someone else's judgment of your vision. Fuck them. This also means be ready for consequences of your decisions.

That said, sometimes you owe it to yourself (TO YOURSELF, not another person) to apologize. Which basically means you're apologizing to make yourself feel better. I would in fact argue that > 95% of the time, there's nothing to apologize for other than someone's else's feelings.