Looking for a book to help me stop becoming a jaded, impatient curmudgeon

Lately I’ve noticed I’m becoming increasingly cynical and short-tempered – impatient with people, frustrated with life, and generally fed up with everything. I don’t like it. I don’t want to be that guy who’s bitter about everything.

I’d love some book recommendations that could help shift my outlook, rekindle some sense of patience or empathy, or just remind me that life and people aren’t all terrible.

I’m open to fiction or non fiction – whatever you think might help crack through the crust of cynicism.