Sorry this is long, but this is v complicated shitty situation and I'm trying not to drip feed too much.
DM (65) is terminally ill with stage 4 cancer - still able to get about, but it has spread to her bones and she has 1-2 years max. She lives with my 'D'F (77) in an isolated part of the Uk.
DB (33) and I (29) both live and work in London, and have limited resources.
IMO DF has NPD. DM is a shell, and my brother and I struggle with forming healthy relationships, and I largely blame DF's domineering behaviour.
It's hard to explain, but it's almost like DF is not a real person. It's impossible to speak to him, as he has no interest in anyone else, beyond things that he can boast about to others. He's obsessed with his ex career (he was often out of work) and selective bits of history (Wars and how great the Empire was), and every topic is drawn back to those things within a couple of sentences.
He also says horrible personal things, and can sometimes be very threatening (has picked up kitchen knives during nasty arguments, although has only ever hit my DB) if anyone challenges him. My very normal XDH didn't get this at first, and got called a cunt during our second and last visit for disagreeing with him over types of engine.
After retiring early, DF spent thousands on his hobbies while DM slaved away working nights to cover the mortgage, unable to buy herself new clothes and still doing all the housework.
DF has also been cheating on my mother for years with people he meets on BDSM swinging sites. He made suggestive comments to me when I was a teenager, and I've seen sexual messages to his daughter from a previous mariage (not his bio daughter, but still). Despite this, he has Victorian expectations of everyone else's morality.
I gathered evidence of the cheating and showed it to my Mum in 2010. She chose to stay with him because she didn't want the 'fuss' and for financial reasons, though she didn't even consult a solicitor. I think the reality is he'd ground her down so much she couldn't see a way out.
I couldn't stand being around them anymore after all that, and as a result I've had very limited contact with DM until she got ill. I feel very guilty about that now.
DM is utterly miserable about how her life has turned out. She thought my father would die, and leave her to enjoy her retirement. Her pets and her sister also died just before her diagnosis, and she has no one - my father makes it impossible to have friends or visitors. DM's not been abroad for 30 years because DF didn't want to go. I promised to take her to her favourite country this year so that she could live life a bit, but obviously Covid has scuppered that plan.
While DM's been ill, DF has been doing his thing. He thinks everyone should be thanking him because he does one thing to help, driving DM to the hospital. DF thinks he's iller than her, and that DM 'exaggerates'. He told me that he is the one that is truly suffering because cancer patients 'get nasty' and 'take it out on their partners'. DM is still doing all the housework, and clearing up the messes he leaves in the toilet after she's had chemo.
Whenever she even mildly disagrees with this behaviour, he tells her she's 'abusive' and lacking empathy for him. He is still sexting with BDSM buddies. When DB and I visit, he creates a tense atmosphere, so we can't even enjoy spending time together.
DM understands this is emotional abuse, but she is frightened of what will happen she tries to do anything about it. She keeps saying its too late, and it is her punishment for not leaving decades ago. She's vaguely hinted about killing herself to escape, although I don't think she was serious and she'd never repeat to anyone else.
It's bad enough she's dying at this age, but this is awful. He's ruined her entire life.
I'm particularly worried about what's going to happen to her when she's very ill/dying, and he has complete control of her.
Does anyone think there is anything at all I can do to help her, or had similar experiences? I tried persuading her to move out last year (I could help with most of rent/mortgage as it is a very cheap area), but she didn't want the 'hassle'. I'm at a loss, and very selfishly tempted to just stay away so I don't have to see this play out.