I got a lot of 'but she was still your Mum' when my mum died.
She was alcoholic, manipulative, a narc - since I was 13 she hadn't really been a Mum to me in any real sense except legal duty. Never there when I needed her, cruel and abusive when it suited (and that had been ongoing since v early childhood, not that I properly realised it until my 20s)..
She died of an alcohol related seizure (as best we can tell) she had one about 18 months earlier, was found by her boyfriend and hospitalized... pretended to all and sundry she was fine which, when she dried out of course she was... Went home and continued to drink and then, 18 months later was found by me, on her bedroom floor verging on dead (dead 10 hours later).
I got a lot of guilt tripping, 'oh she was still your Mum' and 'you should have called her more often, gone to see her more often'...
No. No I shouldn't have, and I shouldn't have been made to feel as a child and young adult that it was my responsibility to look after her and take her abuse.
If she hadn't delighted in ignoring calls for days on end, and deriding and abusing at any suggestion anyone was concerned for her well-being, she might not have laid on the floor for 3 days dying.. Entirely her own fault and I refuse absolutely to feel guilty.
I'd already grieved for the Mum I should have had when I was in my teens. By the time she actually died, she was not a Mum in the slightest, she was a vile, abusive person, a danger to herself and others, and she'd been that way through her own choice for a fucking long time.
You do what you need to do, and feel however you feel, there is no right or wrong here, it's entirely up to you.