He's probably not throwing this in your face to cause you pain as his primary purpose; it's his own shame, guilt, and self-loathing that he's trying to deal with. He wants to know what made you the way you are because he wants to know what made him the way he is. Don't take his "Yeah I'm a f**king fag, and I don't like it" as a condemnation of you any more than it is a condemnation of himself.
When stresses come along, families generally either fall apart or come closer together. They often are too caught up in their immediate response to give any thought to how they react. Don't do that. CHOOSE to become closer to your brother (he is, after all, your identical twin), and become closer to him. Whatever pain you're feeling, he's almost certainly feeling worse. At least you had Green when you came out, and you have some measure of happiness and freedom now. Your brother is many steps behind you, and is handicapped by being a cold personality (or at least, he CAN be cold to people), which means he has less of a support network than you do.
At any rate, call him to reassure him that you didn't walk away from him because you rejected him for being gay, but because the combination of sympathetic pain and remembrance of your own pain was too much.
Eventually, the emotional pain will pass for both of you; but if you share the burden, it can go faster, and maybe bring you closer together. My sincerest best wishes to you.