There is a lot of information and opinions thrown around TB about the subject of what it takes to make it, how bad the odds are etc.
I just started reading "The Big Gig:Big-Picture Thinking for Success" by Zoro (drummer for Lenny Kravitz, Bobby Brown, New Edition, and many other big names). It's already a fantastic read, and I highly recommend it to anyone who may be interested in checking out, or continuing to pursue a professional career in music.
It includes QR codes for dozens of short videos, and I wanted to post this one from the first chapter which really nails a lot of the reality of the ups and downs, and the deeper, higher meaning in being a musician:
Chapter 1: The Art of Accompaniment - YouTube
I hope it will inspire you like it has me.