Hi ed. It's a sad and difficult situation, and all you can do is try a few things...
There was no way my mum was ever going to see a doctor about the many problems she was experiencing due to her Alzheimer's. As far as she was concerned she was fine, and there was absolutely no regard for how her behaviours were impacting on the rest of us. She was otherwise healthy, though, and a very infrequent visitor to her doctor's. So I made up a story about the flu being extra horrible that year and off we both went to get the flu jab. At that point I'd seen her GP already, so they were aware that that wasn't the real purpose of the visit.
If that sounds like it won't work, you could speak to her GP (they probably won't say a lot back!) and see if they agree to a home visit under some pretext (new check ups for people over a certain age etc).
You don't say if you suspect some kind of dementia but I'm guessing that's the case seeing as you're here, so you could also identify areas in which both your parents need practical help and introduce a level of carer involvement for her by pretending that someone is going to come in and clean or do the garden or whatever. Sometimes a skilled outsider gets better results than family members.
But, and it's a really big but, even if you get as far as a diagnosis, if she refuses to engage with whatever is suggested (medication, care visits and so on) she will not be made to do anything until/unless she loses capacity. That was the story for me and my mum. She was diagnosed with Alzheimer's but refused medication and every bit of help that was on offer. The only gain was me having access to a very good consultant, CPN and social worker. She wouldn't allow them to help her, but they helped me a great deal.
The only other thing I'll mention is that if your mum's problems are dementia related then things will progress and change, and people can become calmer and more compliant as they move through the stages. It doesn't help the situation now, of course.