Don't feel bad, it is not your fault.

You've tried your best to help them.

I think it is a problem in Chinese culture. First it is a bit too much to just a kid to live in a relative's house for any reason. Second, nowadays most Chinese are very snobby, you are probably not rich enough by their standards. Third, most Chinese only know how to give or receive orders, thus they don't understand what it means to behave respectfully and how to treat others as an equal.