I think this song is more of a statement on friendships than the relationship in question. Probably had a bad "falling out" despite the guys efforts, and now that the girl has moved on and cares little for the guy("I doubt you'll hear about it") she does things that drive him crazy, and his friends use no "discretion" when informing him about all the things she does now that she isn't with him. That's his "obsession", not coping with the one he'll never reach.
I think this song is more of a statement on friendships than the relationship in question. Probably had a bad "falling out" despite the guys efforts, and now that the girl has moved on and cares little for the guy("I doubt you'll hear about it") she does things that drive him crazy, and his friends use no "discretion" when informing him about all the things she does now that she isn't with him. That's his "obsession", not coping with the one he'll never reach.