This was a good movie but I feel like the reason for Flinch's death wasn't as clear. But tbh I think the reason why Flinch killed himself is because he felt like he was sorta acting like his dad which is the least thing he wanted. He and his sister said that their dad used to beat them and that he was crazy. And Flinch being known as the "freak" and sometimes not having control is what probably convinced him that he was nothing better than his dad.