Damn, is she really 81? Chief, I don't know if you've ever thumbed through a copy of Dostoevsky's literary classic Crime and Punishment, but I'm seeing some obvious parallels here.
Like you, Raskolnikov was a lone wolf. Smart, and driven, with an awesome Adonis ratio, but the brilliance within him was being hampered by an unjust world. And so he pondered, until he came to the realization that in order to achieve greatness, one must be willing to rise above the herd mentality.
Notable figures throughout history are not applauded for their diffidence. Rather, they are revered for their strength. They are respected because their contributions to society outweighed whatever crimes they may have committed in the process. Indeed, great men are not bound by moral norms. They transcend them!
Now, you're no stranger to the taste of the humble potato, but let me ask you this: have you ever experienced the pleasure a buttered La Bonnotte or Andean Sunside gracing your palate? You could get a hell of a lot of top-notch spuds with your mum's inheritance. Shitloads of parmesan to go with them, too. Not only that, but you could buy that premium Twitter account you've had your eye on along with a tub of cheque drops and really take the online fitness world by storm.
Do you not owe it to yourself and, indeed, wider society, to take control of her resources for the greater good? Is it not an outrage that she's exiled you to some far-flung hellhole while she lives in luxury? Besides, a woman of her age is just biding time and waiting for the inevitable to happen. There are ways you could make this look like an accident. Old ladies trip over all the time.