Well... it depends on how I roll. It can collapse, it can destroy your economy, it can reduce your confidence.
Your people's life savings, livestock, family members have been sent to you both for religion and for the state. Exhausted means that the current generation is smaller, poorer, and weaker. Like right after World War I. (well... less because you still have units mobilized).
Let's just say, you'll have possibilities of: Nothing, Losing confidence, losing culture, losing influence, losing economy or losing population. Your people are eager to fight, of course, just squeezing them harder to the breaking point might break them.