To paraphrase the great JP, rejection is extremely hard because it is Mother Nature telling you, through means of a female, that your genetics aren’t worth replicating into the future. And that is a terrible thing to feel. It’s evolutionary biology here, it’s totally normal to feel like life is so horrible after that. So use that feeling for what’s it’s meant to do—change you. Better yourself. Get your sh!t together. Stop drinking or smoking, further your education, get better friends, get in better shape, wear better clothes, read some non-fiction, get smarter, play less video games or whatever little gratification you use. Do all of the above, not just 1 of them. Don’t pretend that it’s okay and your confident—it’s not okay and it’s perfectly reasonable to be unconfident after something like that.