I think you just tell you father or mother about this, because you are younger than your brother and he can broke up with his girlfriend because of football, so it is a little difficult for you to persuade him, of course it doesn't mean that you can't persuade your brother, but you need to have a very good persuasive If your brother can find a girlfriend who is also a football-obsession, it will be very great, so I think you can try to talk to him about find a girlfriend who is also a football-obsession. Or you can watch football games with him and make a rule or schedule about watching football games. If this doesn't work, you can discuss this problem with your father or mother to let your brother can't watch football games on the TV, and don't give him any money to watch football games, one day he will realize that how important to have a normal life and a have a good job.