I'm sorry you had that experience, I can certainly empathize.

Open source isn't working for free, it's working for connections instead of money. I find this way of thinking about it useful: my first order goal is not to fix a bug in the project, it is to do a favor for the human being(s) behind it.

If you're really contributing and aren't getting the reward, by all means, walk away and hack on something else. But it's also important to have some humility, and recognize that most of the time you don't get that reward, it is because you simply aren't being helpful.

The hard truth is that nobody is going to help you figure out how to be useful. They're just going to say no.