Except the situation isn't over when your house has burned to the ground.
Taking the metaphor literally...
You have a family and you need shelter. You need to figure out how to survive without shelter. You need to see what you can salvage. Which means still trying to put the fire out so that some of your things or some of the materials can be salvaged so you can consider rebuilding. You need to start clearing out the rubble so that you can think about eventually rebuilding your house on that land.
Yes, it's discouraging, yes it's demoralizing. But humanity (and individual humans) has faced all sorts of extreme adversity over our history. As living creatures we have a survival instinct that requires us to continue fighting. Yes, this particular crisis is our own creation. Yes, it will damage the Earth and our specific ecosystem more than any other action we've ever done in our short time here. Yes, we might have a generation or several generations globally who will have a worse quality of life than the previous one for the first time in several hundreds of years. Yes, it's frustrating that this was caused by selfish greedy humans who will never be held accountable for it, and who will most likely have to coexist with, and collaborate on solutions when they finally decide when it's too late.
Nevertheless, we persevere, and we each do what we can to minimize the damage, to innovate solutions that may protect that what remains, and we think long-long-term.
Our ancestors frequently knew that they were a part of something much bigger and that the impact they could have had on the world or improving the lives of their children were miniscule. Yet they did so anyway. We have been brought up in a generation of boundless optimism thinking that we would all change the world for the better, while living in continuously growing prosperity. Not all of that turned out to be true. That's okay. We still keep going.
Understand, I did not start out with this point of view. I'm not an optimist by nature. I spent years being depressed and fatalist as you might be. I chose this mindset as a survival tactic. But I do believe everything I wrote.