"I'm sorry you're feeling bad about what I said, but I'm not sorry I said it." This will go down in history as the worst apology a partner has ever given me. And, apparently, this failure to acknowledge responsibility is just one of many mistakes we make when we apologize to our partners.
According to a recent study in Negotiation and Conflict Management Research, there are six crucial elements of an apology. Most importantly, you have to acknowledge your responsibility for hurting the other person (which my ex-partner failed to do when he said he was sorry about my feelings but not his actions). Second-most-important is that you offer to make it up to the person you've hurt. You should also express your regret, demonstrate an understanding of what went wrong, state your desire to repent, and ask forgiveness. Yeah, so a plain old "I'm sorry" won't really do it.
But that's what makes for a good apology. There are also a whole of ingredients that go into a bad one. Here are some very common mistakes people make when they're "apologizing" — because sometimes those quotations really are necessary — to their partners, and how they can actually make matters worse.