Who pays for your cell phone use, also does your special interest cost money. If you fail to pay your way in life and are getting someone else to cough up money for you to indulge your love of music via the cell phone then your mum has a perfectly reasonable point.
On the otherhand if you pay your way and you do not impose a burden on your mum then your cell phone use does not involve her. But to be paying your way you need to make sure that you are paying your fair share of the household bills if you live at some and doing your fair share of the housework.
I think it is important to understand that a special interest is not a license to do as you wish, I am sure that my wife would be quite rightly displeased if I spend all my time and all the family's money on my special interests.
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Health is a state of physical, mental and social wellbeing and not merely the absence of disease or infirmity
I am not a jigsaw, I am a free man !
Diagnosed under the DSM5 rules with autism spectrum disorder, under DSM4 psychologist said would have been AS (299.80) but I suspect that I am somewhere between 299.80 and 299.00 (Autism) under DSM4.