I don't see why people are leaping to the conclusion that you've screamed abuse at her... did you? I've assumed you've just bluntly said 'look kid, you smell pretty bad and need a bath'...
This might sound daft but, at that age, I did need telling, a 'ok now it's bath time/shower time' or 'get in the bath at 6' or whatever.
At home, no one did, my parents were/are fairly soap dodgery, bathing a couple of times a week, weekend and midweek... strip washing the rest of the time but I did not witness that, as those things happened after my bedtime/in their own room.
There was no scheduled 'bath time', and everything in our house ran late, so there never appeared to be a logical time to bath.
When staying at friends houses, I'd be told.. 'showers are at x time, get in the queue' or 'we shower in the morning' or 'when would you like to bath/shower, do you need help running the bath/seeing how the shower works' and so I never had any issue bathing/showering when staying with friends.
so could that be an issue, she's just unaware of WHEN she has time/bathroom access to do this?