Whenever I made a mistake I was aware of during our marriage, I apologized. Therefore no reason to apologize for those things again.
None, not one single thing, of what my mlcer accused me of was anything I had done. They were all things HE had done. I felt no need to apologize for those things either. And I have no need to take on his projected issues as any problem of mine.
Can I think of things I might have done wrong in his eyes? Yes, but if he never mentioned them, we're they actually "wrong" or do I just imagine they might have been? I see no need to apologize for something that may or may not have been an offense. And no one can tell me that.
I can only truly apologize if I know what it was I did to hurt someone else and agree with the assessment. My being quiet my be hurtful to one person and a relief to someone else. An apology for being quiet might not be appropriate.
If a person knows they were rude, or spiteful, or absent in their marriage, they can apologize if it makes them feel better to acknowledge their shortcomings, expecting nothing in return. Take that knowledge of what you want to do differently and do better moving forward. If the apology helps positive change, why not?