Diedrich Theile & Lizzie Fuhrmann's marriage was reported in a little paragraph found in the local German papers, but you can now find the info. you've requested transcribed from the State of Wisconsin records on the Family Search site. There were also death notices for a Dietrich F. Thiele in the German papers in 1923.
There are about 225 Fuhrmann entries, including possible matches for Lizzie's parents in: "Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950). The same could be true of Diedrich Thiele's parents.
For more specific information contact:
Gary Rebholz, compiler/editor
Indexing Milwaukee's German newspapers continuously since 2007... helping to access our historic German-American culture.