I'm hoping I can get some advice about the situation my very lovely MIL is in. Her husband (my partner's dad) has always been controlling and got his own way with things, kept her away from the finances and basically conditioned her to accept being in a subservient role in the marriage. In the past 18 months he's become unwell with various complications and she has been caring for him. During this time his behaviour has become really vile and abusive. She's been doing everything for him up to and including wiping his bottom, while being subjected to awful verbal abuse (on one occasion he said he would nail her head to the wall but that would be a waste of a good nail 
).
He listens in on her phone calls and tries to stop her talking to people by constantly shouting and banging with his stick. Their house is in serious need of work which he won't authorise paying for despite being very comfortable, wouldn't let her get a cleaner despite the fact that she's a full-time carer for him and having to do huge amounts of extra laundry for him, and has really awful sciatica from lifting him. He accuses her of spending money frivolously which she doesn't at all, makes her pay for big household items out of her pension while keeping hundreds of thousands of his own savings. It's 'his house, his money' despite the fact they've been married for 40 years.
Basically, he's a weapons grade cunt and she's been calling us anxious and in tears not knowing what she can do about it. We've tried talking to him, writing him a letter, family meetings, talking to the GP. Social services are now involved and have been helpful, but it seems their hands are tied unless he becomes physically abusive. He has a legal right to live in the house, and she won't leave as she'd have to re-home her dogs and I just think it would all be too traumatic for her.
She's finally had some respite when he went into a rehabilitation place for the last three weeks but is due to come back on Monday. He had agreed to carers coming in but has now refused to sign the paperwork saying he doesn't need them, and doesn't want to spend the money which is about £250 a week and definitely affordable for him. She's dreading him coming back but the home he's in don't do long term care and say they've done all they can to help him regain his strength. The physiotherapist also commented on how manipulative he is and said it's one of the more extreme cases she's seen.
As far as we can see, the only thing she can currently do is refuse to be his carer when he returns and just try to live with the behaviour as best she can. We try to give her as much emotional support as possible and help her to see she doesn't have to do as he says but she's such a gentle and unworldly person, and I think she will find it very difficult not to fall back into the dynamic when he's in the house again.
Any thoughts or advice would be much appreciated. She's a lady in her seventies who has been a housewife all her adult life and has a fairly traditional worldview so we don't want to alienate her by being too overtly 'feminist' but she does listen to me and has realised how unacceptable it is. We just don't know what the options are to advise her though.