Greetings Mairi,

Lomira and Theresa are in the Catholic archdiocese of Milwaukee WI. Some early marriages and baptisms might have occurred in nearby Fond du Lac and Washington county parishes, same archdiocese.

A few years ago, the 10-county archdiocese permitted the LDS Library to microfilm the baptismal, marriage and some other miscellaneous parish records. So you can "request / rent" them for 3 weeks at a time at your nearest FHC.
A full set of these microfilms is on permanent loan at the Hales Corners FHC near Southridge Shopping Center in SW Milwaukee County, along with helpful binders of historical and other user notes, parish by parish.

Before ordering, try the research aid to these filmed records on the FCGW [French Canadian/ Acadian Genealogists of WI] website. Go to <http://www.fcgw.org/>;
then to Research Aids
then to Milwaukee Archdiocesan Sacramental Records.

First use the Alphabetical list, even if the town or parish no longer exists, copying any notes.
Then go back to Place Search, inserting each town's name such as Lomira. After you reach the description, click on "View Film Notes" to get a detailed list of records and years. Note both film number and item number[s], to save time after films arrive.

Have you found anything on this couple on the DJCGS website?
<http://www.dodgejeffgen.com/>;
Hope you find them.