If you haven't been following Japan with Regan (https://www.youtube.com/user/JapanWithRegan), he does a series on his second channel called Rejection Therapy, where the idea is to approach someone in public once a day and get rejected in the hopes that it will help make it easier for you to handle rejection. Here's his newest one and now one of my favorites:
https://www.youtube.com/watch?v=AbJ37RpeRZo
-Rachel
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