It sounds bad and it can certainly bring upheaval in your life and that of your family.
Consider the financial implications of never being able to work agan.
Loss of income, subsisdence level benefits.
No more overseas holidays, forget about paying for children's education. No more retirement savings.
The financial cost is likely to be huge.
As with most types of insurance it's the policy definitions that count.
Many companies sell "any occupation" policies for instance.
Don't know what that means? It means that even though a disease or condition might stop you working in your present occupation, if you're still potentially able to be a cleaner for instance they probably won't pay your claim.
Are you covered?