There is a difference between quitting, and finding another situation that is a better fit. If you have a coach who is relying on guest players all the time, he will find himself without a team shortly anyway. Talk to your DD about continuing to work hard on her skills, and begin the process to find another team if this one is not working out. If you worked for a boss that was making you miserable, didn't appreciate your efforts, and gave you opportunities to prove yourself, wouldn't you look for another job?
In her mind, she is...she puts the practice, critiques herself after her JV games, keep notes on what she wants to improve on and watch softball videos on her own time.
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