*Possible Trigger*
Maybe the seeing-thing is connected with something that used to happen, like maybe she was punished for being out or talking like herself or something like that? Or maybe it plays into her mindset of being the hunter, never the hunted, and the hunter is the one that sees the prey, whereas the prey is never allowed to see the hunter. Or it could have to do with something else, like she doesn't trust you to see her yet, or maybe it helps her feel more in control, or maybe if you see her while she's talking that'll cement the fact that she's real in this body, or something like that.
*End Possible Trigger*
The body thing can really affect an alter. Such confusion can make an alter feel frustrated, angry, cautious, wary, protective, afraid for themselves, etc. So coming to terms with and understanding that whole thing a bit more could help with her behaviour.
I'm glad your kids vouched for you and that you were able to convince her that you didn't lie.
I'm also glad that you'll set a good example when things start to come to light about what happened. It's important to remember that the things we want to do aren't always the right things to do.
~Kyra