The studies on those who attempt suicide multiple times and on the vigorous association between past and future suicidality (even accounting for "kitchen sink" variables) are consistent with the view that people habituate to self-injury and thereby gain the ability to enact increasing severe suicidal behaviors.
That is the main argument of Thomas Joiner’s Why People Die by Suicide. Here is the book’s home page. Here is an excerpt. Here is a summary. By the way, athletes, who are used to harming themselves, commit suicides at relatively high rates.
The traditional economic approach compares the costs and benefits of staying alive, with option value thrown in for good measure. It seems more realistic to treat people as having periodic suicidal urges, but (fortunately) usually lacking the capability to execute those urges. Why some people find reason to work their way "up the ladder" of capabilities is the next question. Perhaps the mechanisms behind suicide have more to do with employment, and with economic growth, than we used to think. Rather than making an analysis of suicide more like modern economics, should economics become more like the theory of suicide?