One simple way to look at it. You work in a place full of people that have illnesses, degenerative physical problems and old age frailty etc etc.
They are one big source of motivation. Good exercise and diet, cannot be guaranteed to stave off or prevent illness, degeneration or frailty, it's not a magic bullet, but it can do so much and for many, it can stave off or slow down progression, of neurological and musculoskeletal degneration before it's meant to happen, or allow you to become old, with potentially much less to worry about than others.
The future is better for many, who are now able to see more of the truth, because technology and your sector of society, has progressed what is known, since the post-war era, allowing more people to have access and more understanding, to knowledge of what is humanly possible and how it can be achieved, or shouldn't be achieved.
You have a perfect environment, to develop a new found appreciation for how you could be living. The answers are right under your nose so often. Why end up like people you treat? Even if some of those people in the work environment, are not part of your brief, they're still there and the ability to imagine them being there, could be evoked pretty strongly, just from the names of departments alone, I would think.
Use your surroundings to inspire and motivate you. Don't settle for average canteen food, or often no doubt bland food, the ailing must have.
Remind yourself, that good health for you, means better care for all, because one person with the right to administer medical attention, that has to be off sick, or even treated by their own colleagues, can't deliver any patient care themselves, thus somewhere along the line, the increased demand on healthy working staff increases, even in a minor way, as does the risk of medical negligence, or risk of decreased welfare to such staff, from more stressful or demanding rotas.
You have the emotional and mental ability to care for others, including your Son. You certainly DO, have the emotional and mental ability to care for yourself too and what better way to increase your ability to want this, than to seek motivation from those who have temporal or permanent physiological issues?
Your inspiration is potentially all around you. You just need to see it

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