Hey Nitin! You're one of my favorite people :) Thanks for the question...
Yes, burnout is a tough deal in open source. I actually talk about this quite a bit on The Changelog episode #246. For me basically, I avoid burnout by being kinda heartless I guess. I just recognize that I don't have the time to take care of everyone's issues for them and I enable people to fix things themselves. So I have a course on contributing to open source and I invite folks to contribute back.
If someone asks a question and thinks they've found a bug, I ask for a suggested solution. In the process they often find it wasn't a bug. But if they do find a bug, then I ask them to dig deeper to find a solution.
I think the main bit of all of this is that you should recognize that you don't owe anyone anything and it's ok to say you don't have time to help them. Work on what you want to work on and let others work on what they want to work on. So long as you enable folks to do their work, they can't blame you for it 😉
Good luck friend!