Kashes: To ask or not to ask

Is it appropriate to speak in a complaining way against the Aibishter, to ask kashes (doubting questions) when others suffer tragedies? To in effect challenge the wisdom of the divine decree?

I recall being told that one can differentiate between davenen  (praying) for the future and complaining about the past:

If the painful events are ongoing and reversible, then we davven and are even allowed to demand (many Tefillos are written in a demanding tone) that from now on these events unfold in a good direction. However, when we hear the news of a final, irreversible event, e.g. that someone died (lo aleinu), the Torah tells us to say “boruch Dayan Emes”—blessed is the True Judge—and accept the divine judgement.

Are there any exceptions to this rule? Cases where we find that even after irreversible events occurred, Tzaddikim continued to complain against the divine decree, to ask kashes?

In any case, even if there is legitimacy to such kashes, they are liable to be atzas ha’yetzer, a ploy of the evil inclination to bring the person to fall:

1. Since by definition such kashes have no answers, or at least no truly satisfying ones, dwelling on them for too long can be spiritually unhealthy. These are, after all, the same sort of kashes that many heretics use to dismiss all religion and all belief in an omnibenevolent Creator and Director of the universe. So these thoughts can lead one to doubt Hashem altogether, G–d forbid.

2. Even if one’s emunah remains unshaken, these thoughts weigh the person down and make it very difficult to fulfill the Torah’s exhortation to serve Hashem with simchah (joy).

On the other hand, it seems that our role is to be the defenders of our fellow Jews, the saneigor shel Yisroel. It follows that if Jews suffered, it should bother us, and especially when the suffering seems unjust—when the righteous suffer. As the angels cried out when they witnessed the slaying of the ten martyrs, “Is this Torah, and is this its reward?!” (Berachos 61b) The Torah seems to be telling us that this was the appropriate response, especially considering that angels don’t possess free will. Granted, Hashem negated this, and responded “Be silent, so did it arise in thought before Me,” but that was a later stage. Although Hashem’s response to our complaint is to tell us to be silent, I don’t think this means that it was wrong to express the kashes in the first place. I think that the kashes are a normal, proper response from a thinking, feeling, caring person who seeks Hashem.

In my humble opinion there is a balance to strike here, where kashes are recognized and deeply bother the person, but do not affect the person in a way that weakens his or her emunah and simchah.