Frank Castle is a man pushed to an tossed over the limit. And he has shown us that he can be the most ruthless an insensitive man the comic worlds been shown. An for a human his resilience to pain an overall punishment is phenomenal. But to the point for a man who has seen his share of hatred an horror he could have gone that route an taken upon his villainous thoughts an taken his pain out on the world. Killing all no matter if they were innocent or guilty, but he has a line he has drawn for himself an he has yet to cross it. Yes he may be the most violent human aside from Moon Knight, but Frank has been through more than any of us could have survived. An more than once came up on top above all else.

He is a hero