I cannot give you a general answer as I think this topic is too dependent on a specific time and setting but also because I never researched about historical suicides in depth. However, I can tell you about a certain curious phenomenon of 18th century Germany; not during war or volcano outbreaks but something that happened in general.

It was called "suicide by proxy" or as the Germans would have called it "mittelbarer Selbstmord". Instead of killing themselves suicidal people would murder others, usually little children, because that would give them the death sentence. Death by execution was more favorable than suicide because a condemned is guaranteed to get clerical assistance, someone to confess to, possibly convert and the (public) execution was believed to purge the condemned and society they live in. They could also get a proper burial on the church premises whereas the bodies of people who killed themselves usually got a very rough treatment and weren't buried in a cemetery. Children were often the victims of this suicidal technique because their souls were believed to be pure, thus they were guaranteed entry to heaven. If the suicidal killed an adult instead that would mean to rob them of their chance to confess their own sins and might deny them the chance to heaven. So choosing to kill children instead of adults wasn't a sign of cruelty, as we'd likely view it nowadays, it was sign of mercy.

This only worked with the Catholic belief system as Lutherans have a different concept of sin (Lutherans believe that sin is inherent to mankind due to the Fall of Man, so they don't differ between different types of sin and a confession could not absolve you from it). People who killed themselves still weren't buried on church ground but this didn't have the same gravity to Lutherans than it did to Catholics. That said, Lutherans did not treat the corpses of suicides much kinder, either, it just didn't have the same spiritual gravity.

I am sure you'll get better answers that stay a bit closer to your question but I think this practice is a very good example to show you the gravity of the taboo that was suicide back then. Some people would rather go out and murder a child, to be executed publicly, instead of silently killing themselves. Because that was the more rational thing to do.

I got all of this from the following paper. I really recommend reading it, the topic is very interesting and the paper is nicely written, too:

Stuart, Kathy: Suicide by Proxy. The Unintended Consequences of Public Executions in Eighteenth-Century Germany. In: Central European History, Vol. 41, No. 3, September 2008, Cambridge University Press 2008. Online: <https://www.jstor.org/stable/20457368 >>

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