A teen has a lot of ostentation that has to confront with. first of all, i think it is the phone. it is just a way to get away from it, and that is your mother. seriously, it is a very big problem. and the computer. oh, my god, mom, did you took my cable again? you hate me! this is just trash. your mother loves you and this is why she is taking your Internet cable. let it go. and the 3rd, but not the last, it is, of course, these new things. like the laptop, and the iPad, and the iPhone, these things that are not that important, but everyone wants them. 
i think is all right to have internet access, but not to use 24\24 hours. and it is the same problem with the phone.