Well said. Honestly my first thought when someone said it looks like finger marks is that it might be her own
Again, I'm not armchair diagnosising a kid I don't know but if she's struggling as much as it seems, it's possible she's lashing out inwardly (just speaking as another lonely kid who went through very similar upheaval at her age - house move, new school situation, too old for the new babies but too young for older siblings, few to no friends - it's a
lot to deal with on your own at that age and her parents just keep shrugging her off
And it's very easy to take your frustration out on yourself when it's only ever you.)