Sorry if this is long ...
DF (79) and DM (77) have been staying with us for about a week over Christmas. DM's memory's not been great for a while, but in the last 6-12 months it's become apparent that it's more than that - she gets confused about simple things, ask questions (particularly about future events like what will be happening tomorrow) 5, 6, 10 times within a single conversation, etc.
The worst thing is that she is horrid to DF. She's always been a little bit short-tempered and he is very mild and patient, so they've always had a bit of a dynamic where she snipes at him unnecessarily (to my mind) and he just takes it, but this has become hugely exaggerated. She's very frequently angry with him for 'not telling her' things about their plans which she has forgotten. She also gets angry when he helps her when she's confused, calling him 'smug', 'condescending', 'so bloody bossy' and saying he thinks he's so clever - really harsh and mocking. Yesterday, she announced at about 4.30 that she was going up to bed. DF gently reminded her what the time was and she just totally lost it, ending up by almost sobbing that she wished he wouldn't be 'so unkind'. The sniping is a bit in keeping with her character - although grossly exaggerated - but the emotional break down (which has happened twice this holiday) really isn't - she's very buttoned-up emotionally.
She's really hates accepting help. She has a real stiff-upper-lip, no-need-to-make-a-ridiculous-fuss attitude which has again become really exaggerated. She's been limping for about 12 months - maybe 18 - and we cannot get her to go and see the doctor. She becomes really angry with DF when he raises it. With DSis and me she's not so angry but is dismissive and prickly and closes the conversation down. I've actually got her to agree that she'll see a doctor about it now, but I'm not very hopeful - I think she was just fobbing me off, and even if not, I doubt she'll go through with it. I'm planning to talk to her about it again before she leaves (tomorrow) and then call her fairly often to ask her if she's been. Our hope is that she'll make a doctor's appointment and then we can brief the doctor beforehand on the situation. Even it this happens, though, I'm not that hopeful - I think she'll just be a bit dismissive of the doctor and not go again.
DF and DM are managing ok at the moment, but DF will be 80 next month and DM is getting worse. I live about 400 miles from them so there's not so much I can do on a practical front, though I'm trying to get down as often as I can. DSis lives near them and is great, but she works full-time and has two kids, one with ASD, and a partner who travels a lot for work, so there's only so much she can do.
DM is a very private person and would hate any of us to become involved in intimate care for her or even to know in much detail what is going on with her.
I'm just not sure what our next steps are - how we support her and my DF. I'd really like to hear from others who have been through similar. DFIL died from dementia recently so in a way we have been through this but the situation was very different - DFIL was quite passive and very happy to take direction from DMIL, so she always organised his care and there was no problem with intervention. I'm really worried.
tl;dr - DM in early stages of dementia; hates accepting help and is constantly angry with DF - what do we do?