Achham, June 29 -- At 14, Susmita Nepali from ward 6 of Mellekh Rural Municipality in Achham, one of Nepal's most remote far western districts, should have been worrying about homework, school exams and the ordinary dreams of adolescence. Instead, she was preparing for a wedding she never wanted.

Seven months ago, her parents and members of her community decided she would marry her late sister's husband, following a deeply rooted but unofficial social practice that survives in parts of western Nepal. The custom allows a widower to marry one of his deceased wife's sisters, with the family often having little say over which sister is chosen.

Susmita refused.

She stood alone against her family, relatives and social pressure. Today, instea...