How can we keep firefighters safe and healthy?

i can't answer your question in very sad situation.

but if your situation is very bad, then you can find happiness by thinking about your past that has full of happiness.

or you should do meditation for some time to get rid off from that bad situation.

answer: when you start thinking negitivly and start having suicidal thoughts

or harming yourself, sadness is part of depression as well as fear and anger combined