Winifred Roper

Looking for anyone who can help with my paternal 2x great-grandmother WINIFRED ROPER.  I am having trouble finding   anything on this lady.  According to census records in the U. S., she was born about 1840. Also according to census records she was born in Donegal.  I have no date of birth/baptism, no parents' or siblings' names, don't know when she immigrated to the U. S.  The first time she appears in any record is when she married in New Orleans, Louisiana, US in 1858.  No parents listed on the certificate.  She had 12 children from then on.and lived, died and is buried in New Orleans.  I have checked every baptism and birth certificate for every child and every death certificate.  Marriage certificates of the children too.  No mention (NONE) of parents' names.  Nothing in census records to indicate anything other than what I have listed above.  I have done a DNA test and I got NO HITS on anyone with the nam  ROPER or anyone connected with that name.  I have also searched Ancestry and Family Search in the U. S.I and Ireland for Winifred, Winnie, Freda ROPER to no avail.  In fact, there are very few ROPERs who come up at all.  

The closest I've ever gotten is a man in New Orleans whose name was  GEORGE WASHINGTON ROPER who owned a millinary store in New Orleans.  One of Winifred's daughter's worked for him as a clerk in his store.  GWR was born in New York, and died in New Orleans.  I cannot make a connection with Winifred.  Also, there is a Mary ROPER who is the godmother to one of Winifred's children.  

Any help to further this research would be very much appreciated.  Thank you in advance.

Julie Campbell Hernandez