I don't know if you ever got an answer to your question about a gravesite for Louise Brugger, but I am happy to share the information I've been able to find.
It appears Luise (Kessler) Brugger married Erhard Kahny on October 11, 1886 in Germany. They immigrated to the USA sometime in 1888, the same year their daughter, Lydia, was born. (Their son, Emil, died in infancy before they left Germany.) Therefore, Louise's first husband must have died in Germany.
From what I've been able to piece together, Louise died in Omaha, NE, when Lydia was 3 years old, so around 1891. I don't have specific information about where she was buried, but either a Catholic or Lutheran cemetery is probable.
It appears Luise and her first husband, Leonhard Brugger, had three children: Emma (b. 1877), Emilie (b. 1878), and Leonhard (b. 1881). Apparently, although they would have been relatively young at the time, for some reason these children did not emigrate with their mother and stepfather in 1888. However, family gossip has it that they did attempt to contact their half-sister, Lydia, in the aftermath of WWII, which is how we found out they existed.
Erhard & his second wife, Johanna Glaser, are my great-grandparents. Do you have a copy of Adolf Gottfried Kahny's "Familien-Chronik"?