My older son's friend was a very, very talented player who went to a JUCO 5 hours away from home a few years ago. He had a girlfriend and friends that he missed. He lasted there about 2 weeks and begged to come home. His mom was very concerned about his mental health. I'm not sure what all was part of the decision to let him come home (not my business to know) but I do know that the parents were very concerned and didn't know what else to do. He has admitted now that he regrets not sticking it out, but at the time...well...it just seemed like the right thing to do.
I don't mean to put a "scary" spin on this discussion,and I'll probably get slammed by some of you for this, but as a health professional, I do believe that the state of a student/athlete's mental health should also be considered. The consequences can be devastating.
I get the whole "the coach is testing out his mental toughness" and my husband has even told our sons that if the coach ISN'T yelling at you, he may not care enough to get the best out of you. It's a really tough balance. The advice to listen, listen, listen is good and I would also encourage him to speak to a counselor. It's OK to admit that this is tough and even overwhelming. There is NOTHING wrong with getting help!