I have now had a chance to look at all of the early civil records (BMD) for Mertzwiller. The marriage record of Johann Jacob Durrenberger and Barbe Beuwé/Bowé on 8 November 1814 does not specifically state that Johann Jacob Durrenberger was a widower, however, the man's name, his occupation, and his signature all match the Johann Jacob Durrenberger who was married to Catharina Bricka.
Catharina Bricka/Brika died in Mertzwiller on 8 September 1814 and her parents were listed as George Bricka and Marguerithe Schliffer (although the mother's name was crossed out and there was a comment on the edge of the record that I couldn't fully translate, but I think that it stated that the mother's maiden name could not be verified). Marguerite Bricka, sister of Catharina, died in Mertzwiller on 22 May 1816. Marguerite, age 47 at death, was listed as the daughter of George Bricka and Marguerite Schlaeferin, and the wife of Michel/Michael Rohr (age 48). Michael Rohr and Marguerite/Margaretha Bricka had at least the following children: Catharina, Michael, Margaretha, and George.
Johann Jacob Durrenberger and Catharina Bricka had at least seven children, the eldest, Jacob, was born (recording date) on 10 Prairial Jahr 10, or about 30 May 1802. As you are probably aware, most of the civil marriage records for Mertzwiller are missing for Years VII, VIII, and IX of the Republic. Since Jacob and Catharina's eldest son was born in year X of the Republic, when Catharina was just 21 years of age, it is almost certain that their marriage record was in one of the missing years. However, there is other evidence that the same Johann Jacob Durrenberger married Catharina Bricka and Barbe Beuwé/Bowé (in addition to his distinctive signature).
Friedrich Kick, age 40, was a witness to the birth of Johann Jacob Durrenberger's eldest son in 1802. In 1804, Johann Jacob Durrenberger was a witness to the birth of a son of Georg Friedrich Kick and his wife Anna Catharina. This Friedrich Kick was probably an uncle of Johann Jacob, although I haven't had time to research the Kick family yet. Johann Jacob Durrenberger was a witness to some of the vital events for the children of Georg Bricka (Georg was a brother of Catharina; from the Tables décennales, he apparently died in February 1841) and Magdalena Beÿer. A Georg Bowé was a witness to the death of the twins born to Johann Jacob Durrenberger and Catharina Bricka in 1806. I haven't researched the Beuwé/Bowé family, but it is likely that this Georg Bowé was a relative of Johann Jacob Durrenberger's second wife, Barbe Beuwé/Bowé.
FYI, the marriage of Jacob Geyer and Catharina Dürrenberger took place in Pfaffenhoffen on 12 February 1833. Interestingly, one of the witnesses was a George Michel/Georg Michael Dürrenberger, age 46, "uncle" of the bride. Since Georg Michael Dürrenberger was born circa 1786-1787, he must have been the youngest brother of Johann Jacob Durrenberger (born 1779), since their father died in 1786. Brian Anton does not have this Georg Michael Dürrenberger in his online database.