The world has ALWAYS been on the brink of calamity. It's just that the calamity du jour affects different groups/people differently. Some are not affected much and therefore do not care as much, and for some it's the end of the world as we know it and a serious disaster. What's different about nowadays is that the group that's going to be negatively affected is much much larger, and includes folk that up till now haven't had to think about it much. I'm with @imoldgreeg on this.

Do what you can in your own life circumstances, and help others where you can without making your own life harder. Don't forget to thoroughly enjoy the good bits of your life too - that's just as important. Possibly even more important. Cos these refuel you for coping with the other shit.