"I do agree that people should take responsibility for what they take, even if it is prescribed. "
You can't screen your own kidneys, though. I'm on medication that can effect the liver and kidneys and mine are tested every three months.
Mine were under performing, so it's been something that's been of interest to me.
Doctors have been encouraged for a number of years to do kidney screening bloods (that's all it takes) for anyone who is at risk. It's also been extended for very overweight/obese people.
We do have a level of responsibility, but so do Doctors and monitoring people comes under that.
She is very vulnerable, not being honest, so obviously needs a high level of support.
OP, having helped relatives and friends in similar situations, I've learned that these situation go the way they go and there is very little anyone can do to change things.