what do i do

okay so ts is super random and kinda scary to me and i need yalls opinions so my first ever bf we dated for an year and we broke the start of ts year and i had no prior exp to all ts so he knew ts and he was trynna be a rlly good bf but my parents are rlly strict and kinda hv a screw or two loose which was the exact opp to his parents so it was kinda hard for me hiding the relationship coz i feel like the risk i took was not worth it anyways so i think the entirety of the year my mental health was like the worst it had ever been and i was actively sh but i wasnt rlly open to him and he never rlly understood coz he never went through all that and he used to say u are only sad coz u wanna be sad and uh i lied to him abt me not sh actively and he could never tell coz i did it on my thighs and i was sa'd by him at first i didnt think it was but i realised that i was indeed sa'd and i dont think he realised it like obviously he isnt completely oblivious but he kept pushing my boundaries and trying to make me feel bad abt not being comfortable doing stuff and now after we broke up he started dating his girl bsf who he told me not to worry abt and she is super gorgeous btw and i am kinda contemplating whether i should tell her and i hv ts friend who is his friend and she is clueless abt what he did to me too and i keep running into him and my heart drops when i see him and i wanna puke and he is in the same apartment so my question is that should i tell ppl abt what he did but no one will believe me and he is kinda popular and i am like a big loser who isnt well known but i dont wanna like tell everyone either but i want ppl to know not that boys who have sa'd get completely isolated coz ik so many guys who have and they never get consequences and everyone talks to him normally and sometimes evn more evn after knowing and js doesn't care