And it made me think about mirrors. I think some people (like my bioparent P) are hammered into mirrors by being disallowed to have any independent thought or action, and others are mirrors because it is an easier kind of relationship than communication and self-awareness. I don't know about nowadays, but when my ex and I were together I thought we agreed on so many things because ze was a mirror. And when I spent time with Ash I thought we agreed too, but ze was just mirroring. And then I wonder about myself -- do I attract these people because I am an easy model to reproduce due to my transparency? Or a scarier thought, am I subconsciously attracted to them because I like being reflected? I think it's more likely that I seek real resonance and used to be fooled by the mirroring -- it has been a few years since then, and I have learned to tell the difference at least somewhat, I think. My current understanding of the way to tell is that if someone truly agrees with me on something, that is true whether I'm around them or not, and whether or not I have discussed it with them lately. If they're just mirroring, they won't spot nuances on their own, they won't seek out more information on their own, and they won't apply it to their lives in their own ways.
ETA: I think mirroring can be conscious or it can be habitual. It's is a really useful skill when talking to a boss or some other non-empathetic dispenser of resources; I think it's only a problem when it prevents intimacy or substitutes for it. I think if you are comfortable uttering disagreements with people, having constructive conflict, and maintaining boundaries that are good for you, it is unlikely that you have a habit of mirroring. But I don't have experience from the inside, myself, so I'm just guessing. I don't think I've ever mirrored successfully, though I certainly try when it comes to job interviews :-p