I respect the other Expert's viewpoint, but I see this differently.
You were at a music concert. People were excited by the music and enjoying themselves. Yes...the woman behind your husband was inappropriate. However, I don't see this as a terrible, marriage threatening action. Yes..to tell her to stop touching your husband was your right to do. And, as you wrote, she stopped. She apologized. End of story.
The issue of your husband flirting and then blaming you when you confront him is a separate issue altogether. What happened at the concert is, in my experience, a symptom of a larger issue.
It seems that you are angry about his flirting, his blaming you, the sense of disrespect that you feel and so you distrust him. These need to be addressed.
Can you say more about what you are feeling? What happened last night was irritating. But it's what is underneath that situation that is really at the heart of the matter.
I would be happy to chat with you more if you would like to explore this.