The inauguration of Venezuelan President Nicolás Maduro has left his opponents grappling with conflicting feelings of hope and disappointment, pondering why the leftist leader could not be stopped despite credible evidence that he had lost the election last year. Some described the mood after Friday’s ceremony at the legislative palace in Caracas, Venezuela’s capital, like an emotional hangover while others said they felt abandoned. Still, many expressed cautious optimism, finding a measure of comfort in the social media videos released by two opposition leaders — popular former lawmaker María Corina Machado and Edmundo González, the opposition’s candidate in the vote — who had promised to topple Maduro.