Her saying that was about her.
She was saying "I can't tolerate it when other person acts in ways that I perceive as being like a belligerent teenager."

I think she could have thought about her reaction more before speaking, and asked herself where that's coming from and what it's about.

When you asked her later, seems like she could have had more to say about it: asked what your perception was about how you were acting, etc.

Therapy can be a hard balance: letting yourself be vulnerable and learning through these kinds of situations how others might be seeing us.

I think it needs to be talked about more because it's not settled with you.