I don't have any information on her marriage.But the family you seem to be talking about is:
Amable/Abraham Facteau (b. abt 1813, d. 8 apr 1898) and his wife Mariam Mongrain (or Moutgras) who d. abt 1845. Their children (that I know about) are: William Facteau, b. abt 1836 Matilda (Mary) Facteau, b. abt 1838 Fanny (Josephine) Facteau, b. abt 1841 Amable (Abraham) b. abt 1842. who m. Mary Racette on 10 Aug 1865 in Redford, Clinton county, New York.
The elder Amable/Abraham married a 2nd time (abt 1845) Marceline (Melissa) Brault they had 17 children, the only one with Mary in her name was:Mary Rose, b. 9 May 1863 in Redford, d. 8 Apr 1885 in Redford, and m. 27 Apr 1880 in Redford -- Peter Henry Beaudoin.
I will be more that happy to share additional information on these families - if you are interested.