This shouldn't be an ethical thing HONESTLEH. If someone in a relationship felt hurt, even if you are right, even if it was a 'misunderstanding', that's not going to immediately correct the course of things, or make them feel better.
The fact is that a lot of times there's always middle ground. One can argue that she misunderstood your staying as leaving her behind; and that you misunderstood her story of the mosh pit as being something worthy of note and playful, but not THAT severe a trauma for her.
But the point is that if you really care for, trust, and are a part of her, then trying to make amends and apologizing must be in the nearing future in your relationship. And then, one day the both of you will look back at this, and all will have been forgiven.
But you must first approach this with gentleness, with consideration -- not bitterness, or compulsion, or anger, if you want that forgiveness to be as genuine and healing as possible.
On the other hand, if the two of you are unable to really work things out after this... well, hey babeh, not all good things last a long time. xP Relationships can dissolve over things we cannot control, over things at the wrong place at the wrong time, over dogs and cats in a tophat. All depends as well on the deepness of the relationship and magnitude of the incident. Maybe it was just not meant to be, and you must prepare to cut things off and move on.
But if you still have feelings for her, and trust her to meet you halfway at some point, then try to reconcile with her, and as best you can, try to offer as little judgement on your part, however true. Sometimes, people get emotionally shaken and they just need some reinforcement. Even if they don't offer it to an equally hurt companion... sometimes for a relationship to overcome its humps, you need to let it be unfair. 'Cause maybe not tomorrow, maybe not next month, but one day, it will be appreciated. And somebody has to be that anchor, if at this moment, she can't.
That or some breathing room could do; some time to think, to yourselves.
G'luck..!