I'm a Rome enthusiast, gradually educating myself on my own.
We've all read of the triumphs, and of course a victorious general would be popular. Something I've started to wonder about was the sentiment of the average citizen when Rome was defeated on a large scale, for example at Arausio or Teutoburg.
I realize it was a different time and completely different mindset, but it still strikes me that military defeats tend to make a leader and a war unpopular in modern times and I wonder if that carries back to more ancient times.
Did the news just spread so slowly that the impact on the people was minimal? Were such losses accepted as part of life back then? Or did popular resistance start to develop?
How would we know what an "average citizen" thought? Every text we have is produced by the elite class. Whether people lost friends or family is impossible to know in the specifics.
We do know that military disaster did not affect the political careers of the generals involved. Rosenstein in Imperatores Victi demonstrates very well that statistically military defeat had little or no impact on the further career of a general. Losing, as long as you got out alive, simply didn't matter.
On the personal level, among the elite, we do have evidence for friends and family grieving for loved ones. Both Catullus and Propertius write about that. Logically you would by extension think the "average citizen" would have similar feelings. There might be stele that can give more of a middle class view of the matter, but I don't know them and I don't have the resources to get them right now.