You have gotten to a powerful place.
We can't help everyone. We can't even help most people. Because most people don't actually want help, or can't process it when they get it.
In my Burningman community, one of the principles is "Gifting". The idea of giving someone something they need, without expectation of anything in return.
This is surprisingly hard for people to do, actually.
The giving part is easy. People give other people things every day.
But the receiving of a gift turns out to be where most humans fail. Their immediate reaction is to give something in return, rather than to accept the gift. This changes the interaction from one of GIVING to a TRANSACTION. An exchange in equity, which distracts from the usefulness of your help, and sidetracks the receiver.
(There's also some self-reflection you can do about your style of "helping". Are you trying to "fix" someone, or are you actually giving them the help they can actually use and consume, right now, in their current headspace, etc? Just something to think about...)
I burned out on helping people in the past, too. But I go back, because I find people who are genuinely looking for guidance, support, help, and I get better and better at weeding out the complainers from the people who are actively working to make a change in their lives.
Be with yourself for a while. You get satisfaction from helping, so you will come back to it eventually. Be well.