Non-PRO Japanese to English Art/Literary Cinema, Film, TV, Drama

Dear ProZ members,

I'm in doubt on how to inteerpret the following sentence from a cartoon. A girl comes back home from school and finds her little brother playing videogames with his two best friends. As the three play games almost every day, the girl is very harsh on them, asking if they don't have anything better to do and if they don't have other friends. She says this to the oldest of the three:

あんたも６年なのに大変だね。こんなバカどもと遊んで
(You're in sixth grade, you'll end up bad playing with these idiots.)

I'm not sure about the meaning of 大変 here. It it an admonishment ("you shouldn't waste time with them for your own sake") or a sign of empathy ("playing with these idiots must be terrible for you")? She seems critical with him too, though.

Thank you so much!