You will know when he tells you, flat out. In very clear and uncertain terms.
Basically, until he uses the words *________* (insert your name) and "girlfriend" in the same sentence, you're playing the waiting game.
While actions so speak louder than words, especially with guys, there are still certain assumptions you cannot make without hearing definitive statements. Love, relationship, use of his CDs; none of those things are to be assumed short of verbal confirmation. Written is even better as it can be used in a court of law as a contract.
Hmm...quick question. You wrote this:
I have been dating my ex for over a year exclusively.
So you've gone back to your ex boyfriend and you're exclusively dating but have yet to know if you're officially his girlfriend? That sounds a bit odd to me. With somebody that you're already familiar with and comfortable with, how in the hell is it taking a year to determine your status?
And have you asked? If so, what did he say? Hate to say it, but my guess is that if he wanted you to be his girlfriend, he probably would have said so already. There's no learning curve like with a new interest. You already know what you're getting, save the changes you both hope you've made to make it last forever like a Keith Sweat song in the 80s.
I miss the 80s (even though I was too young to appreciate anything that didn't have to do with Thurdercats, GI Joe, and 3-2-1 Contact).
Anyway, if you're waiting on him to bring it up to you-after a year-you might as well wait on Benjamin Gates to find Atlantis. At least that's got promise. Ask him what's up, and see what he says. If his response has any hint of avoidance or elusivity, or if he comes back with some malarkey like, "what do you mean, where are we going? We're in a good place...etc..."
Basically, if he comes back with anything but a straight answer, well, you've got your answer. It's probably not going to happen.
And thanks for the compliment. Me love you long time.
It was written.