Take it as it is. She owed you, and she paid it. There isn't anything more to read into even if you are tempted to. It won't get you anywhere and it's going to throw you for a loop that is going to have you acting desperately like before and having her clam up on you again. You think you need closure but you really don't. What answers is she possibly going to provide, if she even wants to be honest? As soon as you are done talking, you will still have more questions. It won't get you anywhere.
Simply accept it as it is, she neglected you and didn't feel for you like you felt for her. You can still learn from this. Maybe you can take it slower next time (3 months isn't a long time at all to "spill your guts"). I'm sure you could have approached it better or maybe there were some things you said that you wish you could take back. Also not to put up with this kind of behavior from somebody else as well. All good points to learn from.
Waking up next to a beautiful girl,
Step outside and say hello to my beautiful world.