I have a similar mom & followed similar r/s patterns as you.
I deal w my mom this way: I know what I can and can't expect from her. I can now get a call or card from her & take it in the moment as nice but am detached in a way that doesn't make me get hurt when she withdraws that love as quick as she gives it.
Once I accepted she never was nor ever will be the mom I wished I had had it made me oddly able to see her in a more vulnerable light than I had before & I still have hurts and sadness about so much of what she did to me as a kid but I somehow have been able to see that, feel it, acknowldge it & also take what she does have to offer & leave what doesn't work. Not sure this is coming across clearly. I'm on my phone & very tired do I apologize if I make no sense! There are parts of my mom that I understand better now for having been through what I have w AH & I think she is deeply flawed but loved me in the way she knew how & I choose to accept that & create some kind of r/s in the present that's separate from the past. My father on the other hand has continued to be the same narcissistic ass he always was & the only healthy choice w him is total detachment & NC. Ironically it's my mom who was more overtly abusive to me as
a kid but she has owned that whereas he cannot & thus I have zero need for his presence in my life.
Just my experience & if it helps in any way I am glad.