Junot Díaz's "The Pura Principle" (short story, non-genre, free): Mother's pain from a sick irresponsible grown son
It actually started off bad - too much swearing & liberal use of words from a language I don't recognize, but than it picked up.
A totally irresponsible & mean man is suffering from a serious case of cancer. Lives with his mother & younger brother. Narrated by brother. What I saw here was mother's suffering - I know of similar real cases (without cancer).
Fact sheet.First published: The New Yorker, 22 March 2010.
Download full text from publisher's site.