What shoulf i do

so this is how it went down first i dont know why but i didnt like my stepfdad i had this feeling he use to hit my mom but now he doesnt and i dont know why i didnt call the police and instead i just froze up in fear and did nothing .so first it started with him touching my thigh and i got scarced and got up i said what the fuck do u think your doing and next week i build the courage to tellmy uncles and aunts everything and they had a argument with him(stepdad) but of course my mom was blinded by love but they did tell her about him touching my thigh and after that i was scared to go home and i stayed at there house and now today he touched me fown there trying to make it seem like he didnt mean to but i told him i did you touch ne there he said nothing i told my little cousin and i want to tell my mom but i feel like she will perfer him over me and to top it all off i have a three yrs old brother and im scared i dont know what to. do back then i use to cut my self but my uncles and aunts found put and they made me stop and sometimes i feel like going back because that was the only way to forget the pain .Some times i feel lile my mom would prefer my step brother and stepdad and not me because my dad left her because of me .sometimes i feel like its all my fault i dont know what to do please help me .