I wasn't suggesting you would abandon her - rather that may be a emotional reaction on her part to her experience.
I apologise if you felt I was insinuating that.
Perhaps she is trying to see if Male love exists. However, "adapting" her behaviours to be what he wants isn't really a fair test of that. He should love her for who she is - the good kid, who attends school, doesn't smoke etc.
I doubt saying that will cut much ice though (it certainly didn't in this household).
The good girl element and rebellion is interesting. Teens are at a point of discovering who they really are. Experimenting with their identity in all sorts of ways (physical appearance often being a big part of that, but also things like music, new activities, ditching previous sports etc).
Maybe she's feels she's served her time being "good"? It's a new persona she's trying on for size?
It's hard to know and I think all you can do as I said previously and you want to do is sit down and chat calmly. Ask a few questions (eg I'm trying to do my best as a mum and know I don't always get it right. Can you speak to me about what you think needs to change in our relationship?) and then try and listen to her. She's expecting a lecture most likely IME. Not giving her one and asking her for a path forward might change the dynamic.
It might be worth, if you can, doing this out of the house. DH and I definitely made better progress on neutral territory . It's easy at home to stop talking/listening and stomp off in a strop (the teen not the parent though we were tempted at times!) and going somewhere nice puts everyone in a more receptive mood to start with. A favourite restaurant seemed to work well, especially as you could take time out from "the chat" by talking about the food for a bit.
Good luck 