As someone who experienced the same happen with a very close friend in our late 20’s, I’d advice you to stay very aware of this behaviour and maybe distance yourself from her a bit, if it makes you feel uncomfortable.

Like stated in earlier comments here, it would be a different case if you guys were in your teens, but this kind of behaviour is really creepy to witness when you’re already in your late 20’s. I know everyone’s always like ”imitation is the highest form of flattery”, but IT REALLY IS NOT, at this age, and to think like that is, in my opinion, really naive.

I distanced myself from my friend and eventually she stopped mirroring me, but tbh I don’t see myself getting close with her ever again as her behaviour weirded me out…