Just like life, any level of success in basketball comes with a ton of criticism. The higher you’re ranked, the more eyes that will be on you telling you that you're not good enough. A coach who’s hard on you is not likely hard because he doesn’t like you, but because he sees untapped potential and wants to help you reach it. If you can’t handle your coach being hard on you, how will you handle your critics coming down on you? Continue working on your game until you are harder on yourself than your coach is. Success will come.
Coaches that are being hard on a kid typically do so because they know the kid has a lot of potential and want to push them to be better. Understandably, they are trying to bring the best out of their team. If they're not pushing you to be better, then the sad reality is that they probably don’t believe you can contribute much more than what you are. A good coach will always try to encourage his players, not bring them down. If this isn’t the case and you think the problem is bigger than that, then schedule a private meeting to respectfully discuss your concerns and your future with the team.