It sounds like you're under a lot of pressure. Maybe you just need to make some time for yourself and escape all of these worries. If you're worried about your partner self harming or having destructive thought, that's perfectly reasonable. Is there a helpline you can call locally?
could be over-protectiveness because of the near death scenarios? or if you're constantly worried about his mentality it could make you angry he's putting himself into situations you might think he can't handle?
yeah it sounds like it would hah, but i reckon if its something he loves doing it could be pretty good for him, it lets him vent things out or distract himself
we all go through cycles like this... perfectly normal.
You are mothering him. You need a partner not a child.