So much to unpack here. Well considering Ms. Rose’s age, she grew up pre civil rights era so likely in her mind she had a basic understanding of racism and like most of us her knowledge base stopped growing on how unacceptable it is to use the word now.
Example: Since I have stopped working directly with the gay and trans communities, just saying gay and trans is probably offending someone right now reading because I didn’t rattle off the 2,000 different names and titles people label themselves with. I can’t keep up with them, nor do I try to. I am not trying to intentionally exude anyone from the LGBTQIA community….but the lingo has changed. The people who are offended don’t know anything about my past serving my peeps and I am getting too old for all these new acronyms and names…all they care about is I forgot their letter or sub-group. That makes trying to have an intellectual conversation a no-go.
I would say you handled it well…but consider this. One day you’ll be old, and as you age your interests will change. So will you social circles. Your knowledge may increase or be retained at a level from a different decade because …life just moves faster that we can sometimes. She clearly understands the power of the N-word, and if she was 90 she had the power to use it, heck she was White. I think her mind was in a different era, but your mom clearly sees the good in her, which is the only reason Black folks break bread like that with the Ms. Roses of the world.
As for your partner though…he needs checking in my opinion, especially if he knows how passionate you are about race and equality. That was a teachable moment he let slide. He allowed you to do the heavy lifting. Or maybe he felt like his correction may have been more harmful than her N-Word slip up. Idk…but a chat after you marinate on it is appropriate.