Pretty much the title. Him and Eva Braun knew each other for pretty much 16 years but didn't get married until they knew they would kill themselves the next day (and Hitler was 56 at the time). Geobells, Göring, Himmler, Heidrich, Hess, Bormann, etc. were all high ranking Nazis who got married. Why was Hitler so different in that regard?
According to Otto Wagener (SA Chief of Staff from October 1929 through December 1930), Hitler declared to his party comrades that he was living in politics and rejecting his private life, and had never planned to marry at all. In a personal conversation with him, Hitler said: “I have another bride - Germany! I am married to the German people, to their fate! [...] No, I can not marry, I have no right. "
Nevertheless, relations between Hitler and Brown began to strengthen after 1931, although it is not known for certain how much they became closer and how they developed. During the election campaign of 1932, Heinrich Hoffmann (Adolf Hitler's official photographer, who was a member of Hitler's intimate circle) sometimes took with him "his little lab technician Eva Braun", "which Hitler was glad to see in the evening at the table in order to get a little distracted."
The existence of a mistress did not fit into the successfully cultivated myth of the lonesome, godlike führer who sacrificed his personal life for the cause of the Germany. Only at the end of the war after Hitler's suicide did the German public learn that he had a love interest and many refused to believe it.
Source:
Eva Braun: Life with Hitler, By Heike B Görtemaker, 2011