I haven't found a marriage for them but may have found her maiden name. Hopefully, this site will work for you but I wrote down the info just in case.
http://archiver.rootsweb.ancestry.com/th/read/CAN-ONT-SIMCOE/2008-11/1226145051There were write ups in Nov 2008 on different servicemen from the 116th from the Simcoe area.
Hirst, Charles Hnery
Charles Henry Hirst, husband of Delaine Messier of Penetanguishene, was born Jan 15, 1898 (Ithink this is a wrong year) in Doncaster, England. He enlisted on November 1, 1915, fourteen months after his marriage. He was a labourer and was issued service number 644586. He served as a private in the 116th Battalion, Canadian Infantry. Charles died on August 12, 1918 and was buried in the Bouchoir New British Cemetery in Bouchoir, France. He was listed as killed in action in the Toronto World edition of Monday, October 28, 1918, page 11. His name is recorded on page 429 of the First World War Book of Remembrance.
I went to the Home Children section at Library and Archives Canada and the only Hurst in 1907 was listed as C Hurst and the pages of the passenger list are very poor. It is hard to determine for sure if the C. Hurst is male or female.
I also didn't find him on any census for Ontario or the rest of Canada so he may have been traveling looking for work as he would have been abt. 19 years of age. I didn't find a Delia or near name in Penetanguishene in the 1911 census either but some that could match in Quebec. (Sweetsburg, Missisquoi)
Perhaps someone could check with the records in Quebec for a marriage around August/September 1914.
I would also think that if Delia was still young she would have remarried. The best way to find this information could be through the Penetanguishene library as they may have links to information not available on line.
I am not all that great with info in Ontario but someone may be able to pick up with this information.
www.canada411.caThere is only one Hurst listed in the online directory for Penetanguishene
Good luck.