From what I can tell, you guys are still pretty young, which makes all the difference in what form of tactics you must adopt. In this case, she's interested in you, dude. That's the happy truth. However, I'm going to explain why she's feeling hesitant at the same time. You're just a little beyond the friend zone, and your job now is to escalate it further.
What I can suggest is to STOP treating her so much like an angel, literally. I mean, you're even calling her by that term, dude. The trick to successfully attracting girls is to avoid putting her on a pedestal, and instead show the control you have in your life. THIS is why she's hesitating. She's the one that lifts me up. The one who's voice I continue to miss and the angel who never fails to make me smile. No, dude. Drop that Mindset. Or at least stop saying it to her. I AM THE ALPHA MALE. I AM THE ONE SHE DESIRES. <--Try that instead. 
Take a good look at your chat. You're making it very clear that you want to go over to her place just to see HER. Never do that, man. Instead, make her want you to come over simply because she wants YOU to come over. SHE should be the one to desire your presence, not the other way around.
Judging by her words, you've still got a good chance to try again. Next time, adopt a bit of the Cocky-Funny attitude - tease her just a bit more and stop being so nice. This is so you can eliminate the danger of her putting you in the Friend Zone once and for all. Create a bit more rapport between the two of you; make her want MORE OF YOU. In fact, try to get it to the point where she ends up INVITING YOU to her place. Try to end the conversations first, even when it's just starting to get good. In fact, LOOK FORWARD to ending it while it's getting good to leave her wanting more.
She already sees the "potential" in you, dude. Now take it a step further. It may take a bit of practice and experimentation, but I'm very sure you'll get it if you keep at it. Good luck. 