You may likely have found what you are looking for by now, but thought I'd post this just in case:
Marriage record #012566-78 Andrew Somerville, 21, b. King, res. N. Gwillimbury, bachelor, yeoman, s/o James and Rebecca Somerville, mar. Elizabeth Cryderman, 19, N. Gwill, same, single, d/o Valentine and Elizabeth Cryderman, witn.: Silas Cryderman, N. Gwill. and Mary E. Powers, Queensville. Married June 17, 1878.
I also located marriage records for two siblings of Elizabeth:
#012630-78 York Co. John Cryderman, 27?, Canada, N. Gwillimbury, b, farmer, s/o Valentine and Elizabeth Cryderman married Rose Ann Wrightman, 16, Canada, Georgina, s, d/o Henry and Jane Wrightman, witn: Elizabeth Crittenden, Wm. H. Wrightman, both Georgina. Married Sept 16, 1878, Georgina.
#012592-1878 Silas Cryderman, 25, North Gwillimbury, same, b, farmer, s/o Valentine and Ely married Emily Clement, 18, King, Vaughn, s, d/o David and Sarah, witn. Wm. Clement, Eliz. Clement, both Vaughn, married Oct 1, 1878, Vaughn.
1878 was a big year for marriages in this Cryderman family!
There is another listing but not 100% that it is the same Valentine and Elizabeth --
12/31/1902 Allan H. Cryderman 23, N Gwillimbury, s/o Val and Elizabeth (Archibald) married to Alameda M. Wrightman, 19, North Gwillimbury, d/o Wm. Wrightman and Margaret Harman, N. Gillimbury.
There are two Valentine Crydermans buried in the Baldwin Christian Church Cemetery - 1863-1935 Elizabeth (Sedore) 1866-1927;
Valentine 1829-1913 Elizabeth 1829-1913.
Allan and Alameda are also buried there...not sure if the Somervilles are.
I'm not related to the Crydermans...they just married into distant branches of the family.
I am interested in a descendent of the Crydermans though...Hazel Rutledge Wrightman (married Charles Edward Wrightman) Hazel was the illegitimate daughter of Huldah Cryderman Palmateer. Trying to figure out which of my Rutledge relatives might have been Hazel's father. She was born 1897. If you come across any info regarding her I'd appreciate it.
Thanks.