AIO for breaking up with my boyfriend after finding these texts?

Am i overreacting? i (21F) broke up with my boyfriend (21M) after finding these texts between him and his (25M) cousin (grey texts) talking about a 17 year old girl. i also found out he has been still looking at girls onlyfans after i’ve told him multiple times that it is a boundary for me. for context, his cousin is talking about using the 17 year old as a rebound after his ex cheated on him. And for context on slide 3&4 he is referring to me breaking down crying to him after i found his telegram full of leaked onlyfans girls links. im posting on here because i wanted unbiased opinions because i keep hearing mixed opinions from friends in my life to how i handled this.