There is an excellent book called "Cancer is not a disease it's a survival mechanism" by Andreas Moritz. This is very much worth reading as this man has got a lot of people with cancer better through diet and cleanses and a change in attitude towards it. It really will alter your understanding of what is going on in the body of someone with cancer. It's brilliant.
Also get your cousin to take wheatgrass - both dried and freshly juiced. This substance more than anything else will provide oxygen for the cells and also anti cancer properties like super oxide dismutase, which most cancer cells don't possess. I can send you an article about this if you want but you would have to send me your e-mail address.
It is definitely possible to get better from cancer, even when the prognosis is bad. Read Beta Bishop's book "A time to heal" to see this.
The most important thing is to know why you are doing something and if you know that it is good for your health then keep doing it even if it doesn't feel to have a fantastic benefit to how you are feeling. You may need to do 15 things to get your head out of water and another 15 to get out of it altogether before you are totally well. So see it as a project with lots of avenues rather than trying to find a magic bullet.
Jan Brumfitt