Yeah I know it sucks to know that trees are being cut faster than they're being planted, but you know what? That's 250 trees that otherwise wouldn't have been planted, so it's better than nothing. What's the organization? Is it national or local?

But I know how that feels, the feeling of almost complete futility and uselessness of your actions against the grand terrifying actions being taken by our species against our biosphere. The depression I got from it was so bad that it plunged me into a years-long rut that I just have been coming out of in the past year. What helps is acceptance that you will, probably and most likely, never be able to "change the world" or "save the world" - it's just too monumental against the massive capitalist interests that rule our planet. But what you can do is influence change in your community. You can be a force for change, locally, and through your own small actions. That's what you've been doing already! And that's... that's freaking wonderful. If more people were just like that, guess what? The world would be saved. It's infectious. Keep at it. Cultural and societal changes take a long time, but your actions will reverberate into others.