I have found “Eunice W. Carr, Mrs” listed in three San Francisco Directories
1878: Carr Eunice W. Mrs., nurse, dwl 711 Bush
1879: Carr, Eunice W. Mrs, Nurse, r, 2418 Mission
1880: Carr Eunice K. Mrs., r. 106 Eleventh

Eunice Carr is reported in an 1877 SF Chronicle article as being in San Francisco searching for her husband and children.
It now seems that she stayed on in the city for the next 3 years working as a nurse. This would suggest a more capable and resilient personality than we might have previously imagined.

Ron