hi nichole, seems you are right, you are obsessing over your brothers problem which is not yours to own. from what you described, makes me wonder if he is telling the whole story. either way, i think it would be a good idea for you to explain to him how this is effecting you and that you would prefer him to try to figure things out for himself. there really is nothing you can do for him but you can began to focus on your own life. sorry i don't have answers to your questions. you can't control what he how he lives his life but you can control how you allow his life to effect you.
take care of you, your brother will eventually figure it out.