I'm pretty sure the latter is really common. I've always thought it was my brain generating failure cases for risk assessment. We think "What if I dropped this bottle of water on my lap while driving and crashed?" and then we take more care not to drop it.
Not sure how they could describe suicidality more clearly. Speaking as someone who has also experienced it due to chronic health conditions that had gotten particularly bad for a while.
What the poster is talking about is different, something that occurs in a deep depression where your mind is struggling to find a way out of the situation. Sometimes the will gives out completely and you're just a zombie to the world, only slogging forward out of habit and maybe guilt.