I don’t want to drip feed, but there is a long back story to my DM’s issues with alcohol and general mental health issues.
She did not get help for them when I was younger, and I was frequently exposed to really inappropriate and scary behaviour from her.
She’s an alcoholic and bulimic, and from when I was very young upwards (3/4) I have memories of her drinking so much that she passed out, having to call 999, hearing her making herself sick into the toilet while I was crying outside the door.. more examples than I could ever list, my post would turn into a book. She also told me graphic details of her sex life, forced me to listen to/hear really inappropriate stuff while she was drunk, and then once she sobered up she’d snap back to demanding respect.
The worst part of all of this is that she was SO horrible to me emotionally too. She denies this. If I ever tried to speak about the trauma I’d experienced, she would make me out to be a problem child - make up stories to my DF, her friends, about my ‘behavioural problems’, painted me as a malicious liar, when really I was just resentful at everything she had exposed me to, and I wasn’t allowed to express this. She was really aggressive about that, and had the opinion that while I was under her roof I must show her the upmost respect at all times 
I left home and had a baby, she still hasn’t got help for any of her issues and she has been drunk at family events we have both attended where my DC were exposed to that toxic side of her. I made a comment at one meal out that I was going to leave early - she totally flew off the handle and followed me and DC out of the restaurant with the people I left with, and was really physically aggressive - shoved her middle finger in my face - and she had to be physically restrained by my DF. There have been loads and loads more incidents like this (not aggression towards me, but generally really weird, scary behaviour).
I have tried to discuss the childhood issues within the last year, she seems remorseful but then goes on to say ‘but we had some great fun too, went to xyz on holiday’ etc..
so I’ve given up getting through to her or us ever having a normal mother/daughter relationship. And like the restaurant issue I mentioned above (which happened after I’d tried to speak to her) she’s had several more binge drinking episodes where she acts really irrationally and I find it triggering because of all the shit she put me through when I was younger.
She hasn’t made any progress or improved at all, except making more and more empty promises, which she cannot stick to. I find contact with her to be really depressing and draining - she still has the same attitude of demanding respect from me
and can be really aggressive and passive aggressive if I don’t show her this respect. She’s so sensitive to any perceived criticism (even if it doesn’t exist) and is constantly on the attack. It’s exhausting - DC enjoy her company as she’s fun and high energy when sober, but I feel like it’s reached a point where I need to protect DC from her.
I suppose I just want some views on wether it’s justified that I give up trying with our relationship and go no (or very low) contact.
Just as a disclaimer - I do understand that her mental health issues might not be her fault, I generally try and be understanding of other people’s mental health issues - but the behaviour has just been to damaging.