I am sorry to hear about your wife and hope that things will get back to as anormal as possible quickly.
You may wish to look at the motorhome press, in particular MMM magazine as it often has complete sections on vehicles designed for the disabled. This also includes adverts from Companies offering everything from parts, to complete vehicles.
It appears that the majority of disabled outfits are motorhome based rather than caravan, possibly because the vehicle, particularly a van based model is stronger and can take extra fittings such as handrails and even toilet lifts. Of course the other reason is that the motorhome does not require manhandling, and if based on a camper vehicle, can also be used as a daily vehicle. The vehicles I am thinking of are based on the Ducato van and are about 6 meters long, not VW campers. Any such vehicle is also purchased VAT free, if that is any advantage.
I hope you find something that suits you and allows you to continue camping in one form or another.