A movie about a musician

I just finished watching a movie about a man named Jay who was living with family violence in Parkchester, Bronx. He is a daily commuter of the Lexington Avenue 6 line he takes to City Hall. He goes ahead and meets this woman who lives in Park Slope via the Culver F Line. Jay lives with his parents, his dad acting angry too much at him for being a slack off. His brother Eddie, discharged with the Marines living without a job.

He obtains a pair of sneakers which supposedly cost about $1,000 dollars at his work. Jay goes to a party where another man, I can't remember the person's name, but he threatened to take Jay down if he didn't surrender his sneakers. He leaves after a fight breaks out in the Bronx, New York. Jay has enemies now.

Jay goes to City Hall, in the borough of Manhattan and plays his guitar. He then meets this woman, named Alexandra. She lives in Brooklyn. She's impressed by Jay's guitar skills. They go to Brooklyn.

The violence that Jay has to deal with, later catches up with Jay when he is ambushed by a group of three men who attack him and his friends. Jay is injured from the attack. Eddie just stands outside and doesn't help. Jay's guitar is destroyed later in the melee.

Jay later confronts the group in the Bronx, and beats them up, with the help of Eddie.

Jay ditches his home in the Bronx to hang out with Alexandra.

The Story ends. I know this was hard to follow, but that's all I can remember.