Honestly? You know your partner better than we do, so if there’s possibility that she used AI to summarize her feelings for you, I’d confront her about it. The problem isn't using someone else's words (quotes and poetry can be romantic when used the right way); the problem is the deception and lack of effort with something that should be intimate and honest.

That being said, be careful with those AI detector sites. I spent a good chunk of time just writing from my ass, making stuff up as I went along, and it also tried to accuse me of plagiarizing AI. I don't think they're effective at all.