My brother is an awful person. What do I do about it?

This is a really tough situation your in. The majority of the time people will talk about the importance of family. however that should never be the reason to let someone who is toxic into your life. I don't know your circumstances or your family so I cant pass any advice on. I can suggest that you should do what is best for you, only you can take the best path forward for yourself. It can be hard. even speaking to your friends might help. you should never have to put up with any toxic behaviour form any individual.

Try to understand him, why is he the way that he is, what are the reasons that have caused him to be who he is now ? Trying to understand someone is the first step to acceptance. Of course there are times when they are genuinely not a good person and it is going to take time for them to change but if they are hurting you physically or emotionally, it’s best to take space during that time and maintain your distance and you are always your number 1 priority If even by giving yourself some space and time, things don’t seem better, or like they are invading your space, it’s best them to involve others in your relationship