Sometimes striking back can be a good strategy. However, there are some tactics that can be just as effective such as asking questions.
"Are you aware that what you said was really hurtful?"
"I am not sure I understand what your motive is here, could you let me know?"
"It seems like you want to hurt me, can you tell me why?"
Question asking can divert the other person and even put them on the defensive. It may be possible that awkward questions can produce a level of discomfort such that the person who is inflicting hurt will be motivated to go elsewhere.