The problem with that is the delayed gratification - most productive endeavours these days require months on end of hard work before any reward can be expected - especially if you start out as a non-expert.
Reminds me of the famous toddler marshmallow experiment - how kids able to endure delayed gratification tend to be more successful later in life.
Well anything that goes to this type of excess will be a problem though:
"a puzzle game on her phone that she would play obsessively* -- forgetting to eat, sleep, show up for work, having basic human interaction and even requiring physical therapy at one point for the muscle strain of sitting in the position to play the game for hours on end."
What we are probably dealing with here is more than a simple addiction (to which your suggestion is good and would definitely be in the right direction). What we have is a mental problem that includes addictive traits.
After all the DSM is fairly arbitrary (as are medical definitions).
If only she could bring herself to getting hooked on a creative endeavour, she would achieve remarkable results.