Books for when you feel defeated and lost in life

I find myself in an emotionally complicated situation. Let's say somebody close to me got something that I wanted, after I was denied the same thing. I'm very happy for them but at the same time I feel lost and defeated. And so so so alone. I feel like somebody left behind in life, a feeling that I'm way too familiar with.

I'd appreciate book recommendations that would help me get out of this slog.

Thank you