They made adaptations to the property, they put in a downstairs bedroom, then downstairs wetroom. So we're easily talking £30/40k there, not to mention other stuff occupational health have done.
If you want to know unfair, it's those that are still living in unsuitable accommodation, waiting for years to find a suitable property everyone bids like bad on.
You said you've been given a new (2 yrs old) house that meets your requirements. If it is in band E I'm guessing you have a 4 bed house on a somewhat executive estate, part of the obligations house builders have, providing roughly 10% of the estate to social housing.
You really don't know how lucky you are to have your families needs catered for.
You said the garden was done to be made accessible for you, then it was changed to it was done before you got ill. Either way £9k is a lot to spend on a garden. I'm guessing you did work on it after they added the downstairs bedroom. So I reiterate again you've been really lucky.
There are those of us who sleep downstairs on the sofa because we can't get upstairs. There are those of us who are house bound and can't leave the property even if they wanted to. Even with wheelchairs and the like. Sitting & lying is absolute agony whilst on copious amounts of morphine. They aren't the sole issues, some of us deal with multiple disabilities. Yes we can argue we worked until we were too ill too.
I've faced disability discrimination and it was a lot more unpleasant than having to move into a new build from a house we'd made a home.
You have to buy some extra appliances to fit in the new kitchen, this isn't uncommon in any council house. If you can't cook, why can't your husband or 20 year old chip in and cook for you? Or do you need them to install a whole new kitchen at a height you can work at?
I get that the situation isn't ideal but I also know that if you are severely disabled you'll be getting benefits that cover your children and disabilities. Plus your husbands wage on top. How do you think though, people cope, who don't have all that money and still have to find carpets and appliances?
I would err on the side of feeling pretty lucky they had exhausted all options so moved you to what sounds like a really nice house, that has the room for you to sleep downstairs. So it does sound like a sizeable house to me. Correct me if I'm wrong but for it to be such a high band, the value of the house has to be considerable.