I've been hitting and dating girls since I was 16 and it once happened to me that a woman I somehow tried to flirt with called me brother.

Oh well.. I just act normal and went with the flow.
So I just called her by her name and tried again until she stopped calling me bro and started calling me by my name.

There's no need to go crazy or act violently if a woman you like calls you bro.. if you really like her.. just insist...