Why didn't you try calling her? Maybe she was waiting for you to call? Sometimes the best thing to do is just call instead of getting upset at the possibility that you were being ditched. It is entirely possible that she got in trouble for something and she wasn't allowed to contact you to tell you she isn't allowed to go. I know where you're coming from, and trust me, the worst thing you can do is get upset with her over this. Next time she's online, just calmly as her why she never got back with you about whether or not she could go. Don't let her know you're mad, but, make sure she knows it's okay.
Good luck and Godspeed.
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"Promise that you won't fall for me."
What's that? Didn't hear you.
Too late, too late, too late, too late
Guess what? I'm drunk