To be honest, people who claim they are "brutally honest" are often rather abusive. Such people think that the phrase, "brutally honest," gives them license to tear into someone else. This behavior is actually another form of bullying, and it does not belong in the workplace or any other place.
People who act like this are not likely to change, and that limits your options. On the one hand, if you are in a job where you do not have much contact with him, and the job offers many other satisfying elements, you may be able to hold your nose and report to him.
However, if his twisted honesty is taking a toll on you, then you need to address it. By allowing yourself to be subjected to his unkind comments, you are only going to hear more of them. The next time he launches into you, dig in your own heels and tell him that his approach is upsetting you and interfering with your work, and you want it to stop now.
If it continues, you should speak with his manager. Once you do so, it should not take long for you to figure out your next step. It may be out the door, and that just might be a step in the right direction.
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