can someone please explain the ending to me...

Seemed he was stuck in the loop of deciding if he should kill those that treated him badly or not. The one thing that kept him from doing it was the obsession with the girl. When the girl couldnt say she loved him near the end, he went right back to that place in his head where he kills those that treat him badly but now he sees his girl at the cooler instead of the bitch,and as she told him "you just need the oourage to do the right thing" and he said something like "i have it when i look in your eyes" and she tells him next time he needs courage to do the right thing just look in her eyes.. so he's at the end and he's confused - is it the bitch or the girl and he looks in her eyes and finds the courage to finally pull the trigger, but he's evolved in the story because of her and instead of killing the people he ends his loop by killing himself. Its tragic but in a way he's kinda a hero.