If you’re having an issue with your coach, and you haven’t talked to your coach about it, please don’t talk to me about it. You won’t get anything out of talking to me if you’re only looking for people to confirm what you already believe.
There are obvious exceptions to this rule, but in general, “I can’t talk to my coach about this. He won’t understand,” is simply your fear talking.
Fear of conflict, mostly, but sometimes a fear of being found out you have malicious intent.