If I were you, I will start looking for

outside opportunities.

obviously the problem is with your boss, who is not supportive to his staff. And unfortunately, this is not something under your control. So jumping to other firm may be the only way for you to change your boss.

At meanwhile, if you have strong power at the company (the company need you every much and not easy to be replaced), you can let your boss or even the big boss "sense" that you are not happy and considering to make a move because of such unfair treatment.