The best way to avoid it I know of is to delegate responsibility and find other people to maintain the library with you (and/or charge for development/encourage corporate sponsorships!)
That said, maybe consider doing the best you can to encourage people to work on the issues that come up -- if an issue comes up, prep as much context as you can and hand it to the person if they're capable of committing code. And then, help people with their PRs once they have something up.
Also do things like post about your project in places Java places might look, or going into "Java weekly" style newsletters (they often have a "call for participation" at the bottom).
Oh and don't forget things like Hacktober (https://hacktoberfest.com/)
Good luck out there! Make sure to take care of yourself -- delivering value for free is not something many people do (thanks for even trying!), but doing it sustainably is harder than it looks, much better for the world long term to have people like you not burn out, even if a feature ships 6 months later (or never at all).
The suggestions about sharing the project in Java-related communities are also excellent. Things like Hacktober are also fantastic opportunity to involve more contributors. Thanks for those suggestions.
Your words of encouragement and reminder to take care of myself are truly heartwarming. It means a lot to me that you acknowledge the effort I'm putting into fury for free. I will strive to find a balance that allows me to continue contributing in the long term.
Thank you once again for your kind words and support. It's people like you who make the open source community a wonderful place to be.
But on the other hand, the success of fury does not depend on whether I put in enough effort but on whether I can build a thriving community to involve more people to join us. I must admit that I am still learning in this area and have a long way to go.