Typical conversation with Nmom

My older sister is pregnant, but every weekend she will go home to clean my mom's house and take her out in the car to get groceries or anything she needs (my mom is 67, but she is not incapable, far from being an decrepid old woman, I understand things are difficult when you get older but since me and my sisters where 10 (I am 28 now) we would do all the housework cleaning wise like vacuum and mop the floor- bear in mind she wouldnt let us use mops, we had to get on our hands and knees and use a rag and bucket to mop the floor, and she had crazy high standards, if she ever had to clean she would moan all day 'oh your poor mum, I have to do everything I am in so much pain, you rotten lazy children etc etc)

Anyway while on the phone to Nmom, she moaned that my sister doesn't have time to take her to see me, this is how the argument went:

I said 'well she works all week then she helps you at the weekend, so it's understandable she doesn't have time to drive 2 hours to your house, chauffer you to and back from mine, then drive 2 hours home again'

she said 'well I never asked her to help me do the cleaning and stuff, that's her choice' (i am already raging at this point, what an ungrateful cow)

then I said 'you know when my sister has a baby, you will have to clean your own house'

she said 'why should I do it, your lazy pathetic father should do it'

I said 'well because he works full time and you don't'

she said 'well he should retire already, he is so selfish' (he is the only breadwinner in the family, my mom has never worked, on top of that my dad always did the school runs and food shopping because she can't drive, sure she did used to cook and do laundry, even this she moaned about. Now that all the kids have left home, she still moans she has so much to do even though I know my dad doesn't eat any food she cooks and does his own laundry, so basically she just moans because she has to do things for herself)

I blew my lid. We got into a big argument. Sometimes it's hard to grey rock someone who says shite that is so provocative it makes your blood boil. This is the sort of typical conversation I have with NMom apart from normally I manage to somehow contain myself, she just gets to me once in a while. I know this will blow over but I am an independent adult now, I don't see my NMom very often, I choose LC over NC because she's not in a position to be super intrusive in my life and apart from being really annoying, she isn't ruining my life. I think LC is kinda tolerable, NC seems a bit extreme. But if every contact I make with her about grey rocking through it, what's the point? Normally people go NC after an explosive episode with their Nparent, and I have done so in the past. But I am thinking I should go NC more and more just because I can't be bothered with NMom, she doesn't add anything positive to my life and not seeing her wouldn't affect my relationship with other members of my family.

Is there any real reason to have an Nparent in your life? Even if they aren't having a super destructive effect on your life....it's like...why would we continue doing something is at best tolerable and at worse soul destroying? I guess cos it's kind of a social norm to speak to your parents? I dunno.

Thanks for listening.