16 year old boy defending him self from recieving bodily harm from step father?

i need help on this matter, okay so if my step father who isnt officialy my legal guardian hit me in a manner that could make me believe that my life was in danger such as punches to the face and chest and strangling could i defenx myself without getting charged with anything or breaking the law because my step father is verbally abusive physically abusive and emotionally abusive he will not attend any family conflict resoulution from physchiatrist or theraprist and evrn if his attendence is mandatory by the decision of a court he will not change his abusive ways. PLEAEE HELP ME im not a bad kid ive never broken any laws And get decent grades please email me or just post your answer please hes threatening to try and force me to be put in an insane asylum as a way to get me out of hs house . please give me ways to get the law to punish him oh by the way he partakes in illegal activities such as pirating many wii, xbox games and pirating movies and selling them to put money in his own greedy wallet he also is abusive as mentioned above any help is appreciated THNX