How 'bout just setting aside the pipedream of changing the world? People have been trying to do that from the dawn of history. It always ends badly, often with such fine humanitarian incidents as Napoleon's destruction of much of Europe and Mao's slaughter of tens of millions.
The world is so much bigger than anyone it doesn't much care that a few misguided people are always trying to change it. They sure can make life miserable for other humans while they're trying, though. Why don't we just make our own little corners of it better as best each of us can, and let the world take care of itself? Both it and we would be better off for that.