<human>: I'm a 22 male, she is 19; we've been in a healthy, committed relationship for just over a year. 

Over the weekend, my girlfriend went on a vacation to San Francisco with her sister and cousin, mainly for the gay pride festivities. I'm excited for her and I genuinely hope she has a blast, but one thing is making me a little uneasy. 

Last night I received a text from her stating that she plans to wear nothing but a bra and skirt to the gay pride parade, which is today. She reassures me that the majority of attendees will be scantly clad and she simply wishes to fit in with the crowd while having fun. From the few pictures I've seen of the event, it is mostly the parade participants who are dressed that way, not necessarily the bystanders. She isn't participating in the actual parade.

I respond by telling her it made me a little anxious, to which she was quite understanding of, asking if I'd prefer her to wear something else. I told her that I didn't want to control what she can or cannot wear, to which she thanked me for. 

I trust my girlfriend and I don't suspect malicious intent - there's just something about the situation that doesn't sit right with me. If I were actually present with her, this would be a non-issue, of course. 

I just feel as if some boundary or principle is being broken. Thoughts? Am I just being too controlling/worrisome?

Can you condense the text into a few key points?
<bot>: Girlfriend is wearing bra and skirt to pride parade without me, I told her it made me feel uneasy but that I do not wish to control what she can or cannot wear. Somehow I feel a boundary is being broken.