Pretty much the same here OP.
Father worked full time, but was pretty much absentee because he spent most of his free time in the pub. He wasn't abusive when he was around, but he was constantly in hot water with my mother because of his drinking, so he wouldn't stand up to her even though he was the more rational and even-handed of the two, and often made it clear to me in private that he felt my mother was being unreasonable. He still deferred to her though.
My Mother. Jeez, where to start?
I acknowledge things were not easy for her because of my father's alcoholism, and she suffered horrendous PND after my own birth and that of my mush younger sibling, however, she never made any attempt to hide the fact that my sibling was the golden child, much favoured, and could do no wrong.
My mother had a default setting of 'no to every request', and if you had the temerity to state that you were hungry, thirsty etc, it was commonplace to receive a volley of abuse in return about what a spoiled, moaning-faced brat you were. I quickly learned not to expect anything from my mother. Not just in terms of asking for things the way children do, toys, clothes, trips to places, outings etc, but also simple basics like asking if I could have a drink, a sandwich, go out to play, make a telephone call etc. She used to give my father a rundown on all my supposed transgressions that day, and to be honest, it was nothing more than a pathetic stream of petty gripes about things that are perfectly normal for a child. There was no give-and-take with her, everything was absolutes. Later, once I hit my teens, I had to listen to the various proclamations about how each of my friends was obviously a trouble-maker (untrue), how if I was out at 8pm I was clearly up to no good (again, untrue), and if I happened to have done something that she felt was particularly egregious, such as waiting until the house was empty to make a telephone call in peace, I'd have her sticking her own face within an inch of mine, before she proceeded to belt me open-handed around the side of the head several times. She stopped this once I grew up at 15-16 and towered over her.
Just like your own mother, I got no warmth, no encouragement, she never had the slightest interest in anything I was doing, my school work, hobbies, interests etc, unless of course there was something negative to report, in which case all hell broke loose, I was treated like a Nazi war criminal, and I'd get all sorts of restrictions put in place such as no going out, being told I was an embarrassment etc etc. This could be as simple as something like putting a used teaspoon in the sink, something my father and sibling did all the time, but that was apparently permitted for them.
She used to tell me things like men who had pierced ears were secretly homosexual and that I shouldn't befriend them, the city I wanted to move to was the AIDS capital of Europe (yes mum, I'm going there for the express purpose of contracting HIV), and that my friends were 'spoiled' and their parents 'weird' because they did things like take them to sports clubs, pick them up from train stations etc.
There was no consistency with her. I got screamed at and thumped for things that my Father and sibling did routinely that went without acknowledgement. She'd complain I was at home constantly, then complain that when I went out I was never at home. She'd invite people around the house, then sit in front of me and give them a run down of everything I'd done wrong recently, all my faults and bad habits, etc. Apparently ritual humiliation was supposed to teach me something, even though 99% of what she was complaining about was either completely overblown or untrue entirely.
I don't recall a single occasion in which I can remember her offering me a cuddle, a ruffle of the hair, or anything that you could describe as warmth or affection. Fortunately I had a godparent who was the polar opposite of my mother, so while it was a relief to stay with them from time to time, it also served to show me just how abnormal my own parents were. Once I met my ex-spouse I was utterly astonished at how close, supportive, and interested their parents were, and they were forever more of source of parental support that my own pair ever were.
I too feel absolutely nothing for my mother, even after the death of my father a few years ago. She has never at any point in her life provided me with any support beyond clothing me (usually in second-hand cast offs), feeding me (with the cheapest, nastiest crap going), and housing me (in freezing cold building sites miles away from any of my friends, my school, or anything a child would be interested in).
I don't feel guilty about it any more, even though I did used to get upset about it years ago. She's not the sort of person I'd usually choose to spend any time with in any case, so I just consider her an acquaintance that I don't have anything in common with rather than a close family member. My sibling says that she has somewhat redeemed herself since they had children, and seemingly she goes over and above as a Grandmother, but to be honest, I couldn't care less. I do not need a mother now, I'm old enough and gnarled enough to look after myself. I needed her when I was a child, adolescent, and young adult, and she spectacularly let me down in that regard, so I couldn't care less what she's about these days.