Quick note regarding the medication issue. My husband was medicated for ADHD when he was a kid, on Ritalin. It damaged his liver and made him insane. He began abusing alcohol at the age of 14. He is against us using meds since our son only has ADD-inattentive, he doesn't have the H part where there are problems with impulsivity and hyperactivity. But, my husband is also currently on medication for his anxiety and depression(yes, all these disorders come from his family line) and he is really having severe reactions to the meds. He has developed sleeping problems, weird manic behaviors, his ADHD is at an all time high and he jumps around from one thing to the next and then back again. It's really driving him crazy. After seeing this, we have decided that meds are risky, even for adults. Withdrawal is also a problem on many anti-depressants. Sooooo, I'm not saying that we'd never medicate him. I'm just wondering if someone can succeed at competitive tennis with an anxiety disorder. He already swims, he hikes with me weekly, we mountain bike as a family, and we work out at the gym. But, he LOVES tennis and the friends he's made. It's the place where he feels at home despite the anxiety. Also, he threw up before soccer matches and football games when he played those sports so it's not just limited to tennis. If he was on a swim team, it would be the same thing. Once he's on court the anxiety is fine, it's the pre-game jitters that get him. On court, it's the attitude and the pressure he puts on himself that become a problem.
To address a few other questions: we always tell him he can quit tennis any time. We tell him we want him to win because we know it feels good to him but we also want him to do what his coach tells him and if he's applying a new technique and he loses, no problem. You have to lose to appreciate the wins and the biggest thing we tell him is 'Have Fun'. Yes, tennis is a competitive sport but we want him to enjoy it, too. We also try to harp on the fact that rankings aren't everything. He has chosen this sport for himself and we've exposed him to every sport except baseball so that he could decide what activities he likes to do.