I'm also sorry to hear about the problems you have been having.
There may be some benefits that you can claim that are not affected by your wife's earnings, for example personal independence payment or benefits paid based on your national insurance contributions. You may also qualify for part help with rent or council tax even with your wife's earnings taken into account.
So I think you need a full benefit check to see what help you can get. The best people to ring are Macmillan Cancer Support on 0808 808 0000. The helpline is open Monday - Friday 9 - 8 pm. They will be able to do a full benefit check, help you fill out any forms and also see if there are any other grants or payments you may be eligible for.
Good luck and do post back if you have any other queries.