On the other- On an aircraft, if you're in a situation where oxygen masks drop, you're always reminded to put your own mask on first before helping others with their own masks. If you did it the other way around you'd likely pass out and not help anyone.
I've been using meditation to train the less controllable parts of my brain to shut up when I need them to. It's been said that mindfulness meditation can make people more selfish, but if I'm passing out trying to help other people, the best thing I can do for my community is to first make sure that I'm a self-sufficient human being physically, mentally and materially.
Since some of my beliefs are wildly unpopular, this often winds up in me feeling ostracized, rejected, and depressed.
In this case, the phrase "speak softly, but carry a big stick" sometimes applies. If you're somewhere where there's enough cultural / social resistance to an idea, particularly among lots of people, you're probably not going to get anywhere, as you've already found. Potential alternatives include talking to individuals when you're able, helping individuals when you're able, if only by letting them know they're not totally alone, and by operating on that oxygen mask principle again. If no one's gonna do anything, sometimes you need to do it yourself, but it might take a long time to get there.