It wasn't even his fault..

---

He was scared, he don't know what to do.. he heard his friend, Billy (your friend as well(?)), telling Sam to not be scared and try to at least man up.

S: "I'm sorry.. I know I don't want to be a coward anymore.."

B: (serious tone) "C'mon, at LEAST try NOT to be scared."

S: (sad tone) "Fine..."

Sam runs away and went to his room in his house, crying..

S: (crying) "This is all my fault.. I'm such a failure..."