Imagine a fantasy hero with a 'time reset' ability like the protagonists of Groundhog Day or Edge of Tomorrow: they can 'rewind time' up to a few hours, resetting their own physical state and the rest of reality to whatever it/they were doing previously while preserving their memory of events, allowing the future to re-play in the same or different ways. Unlike those films, however, the character is not locked into reliving the same day, this is just an ability that's always there for them in life. In my particular idea the character doesn't need to die in order to trigger the effect, they can do so 'at will', but the same question applies in both cases:
How can I avoid having this character sound
like a psychopath completely bored all the time?!
It's completely reasonable that a person living with such an ability would develop a complete dispassion for death and personal injury. Yes, they can still be hurt both physically and mentally, and pain is still painful, but all but the most abrupt injuries are equally unthreatening. Similarly the character doesn't really need to fear the short-term consequences of their actions - they can just reset away from any bad experiences.
These are personality traits that I'm finding hard to express without the character coming off as having no real investment in the situation. Obviously it would be very easy for such a person to actually turn into a pretty unsavoury character, but assuming that they have enough moral Plot Armour to remain a vaguely likeable protagonist, how can I give their thoughts enough depth?
For example, my character stumbles upon a thug holding up a store. She would have almost no hesitation in diving in to try and save the day: any disparity in strength or situation is a fairly minor concern; her only real danger is if she gets shot specifically in the head, otherwise she can just replay the situation as many times as it takes to get her desired outcome. But whenever I try to write an internal monologue of such a situation, it either seems like she's not thinking at all (which is certainly not the case, in fact she's thinking furiously), or that she's just completely dispassionate and unfeeling. I want the monologue to still feel adrenaline-fuelled and emotional, it would just be emotional in a subtly different way to what a 'normal person' would be feeling in such a situation, and I'm struggling to get a handle on exactly how.