Do operas often have unhappy endings?

It depends. There are many different types of operas, and they can have a variety of endings. Some operas do have unhappy endings, such as La Bohème or Madama Butterfly, where the main characters die. However, other operas have happy endings, such as The Magic Flute or Così fan tutte, where the main characters get married or otherwise find happiness. Still other operas have ambiguous endings, such as Don Giovanni or The Rake's Progress, where the fate of the main characters is left uncertain. So, while some operas do have unhappy endings, it is not true of all operas.