In my opinion, for what it's worth (not much), I don't think you did anything wrong. You were honest with your FWB and she doesn't want to commit; no harm, no foul. She has no reason to expect to be able to go to the concert with you.
However, you clearly enjoy being with FWB and she doesn't seem to be in the same place yet. That's the issue you have to address (and that's why you were drunk and texting). Given what you said in your last paragraph, deep down you understand what's going on. I can relate to all of the conflicting emotions. Maybe after this little episode the FWB will have a change of heart.
