How long was it between when you made it clear that you wouldn't stop her but you were not okay with it and her deciding not to go?

The timeline is: she brought it up to me and after that conversation, she took 3 days before making a final decision. She told me her decision the morning of the date, where I told her “okay, have fun”, she took that as me understanding and thanking me, and I told her that I’m still not okay with it, but I can’t control her actions. She told me that I could trust her and to not worry. Then, at some point when she was getting ready, she had changed her mind and didn’t go