sue13 on Family Tree Circles

Mary Anne Murray (daugher of Thomas Murray) was married to Ralph Danskin in 1863. She appears on the 1871 census as his wife. In the 1881 Census (surname misspelled as DAUSKIN), Ralph is shown as married but Mary is not listed. On the 1891 census, Ralph is shown as a widower. Their youngest son was born in 1875. I cannot find any record of Mary's death between 1875 and 1891. Any ideas?