How do other primates behave in this regard? I'd expect various coping mechanisms exist to reduce stress becoming so high that the individual contemplates suici

How do other primates behave in this regard? I'd expect various coping mechanisms exist to reduce stress becoming so high that the individual contemplates suicide as a solution, i.e. I'd expect it to be more common the individual experiences cognitive dissonance, followed by denial, withdrawal, misdirection, etc. to avoid having to directly deal with the stress inducing information/situation. Suicide requires planning, so it's a very cognitive process, where many of our coping mechanisms are more automated (even if learned, typically that's at a very young age).