After her husband's death from cancer

[Bassim]

Have I made any mistakes?

After her husband's death from cancer, Maria hardly ate anything. Her health was deteriorating to such an extent that at one point she ended up in casualty. If it had not been for her sister, Linda, who took care of her, Maria would have likely shared her husband's fate.

 

[teechar]

You need "deteriorated" instead of "was deteriorating" in the above.

 

[Tarheel]

in casualty - in ER

 

[teechar]

ER is AmE; "casualty" is fine in other varieties.