I'm usually the first to call out for reporting benefit fraud but the way you have described this person, sounds like me.
I have a physical health condition but to most people, I probably seem like I'm doing just fine. because I want to portray that image. I travel on foot, decorate etc etc but because I HAVE to
What people don't see, however, is me sobbing in pain, is me on the days when I don't leave the house because I literally cannot walk, is me frustrated because a task really needs doing and I am unable, me feeling like shit because I'm having to ask for yet another favour from my family, me not wanting to try dating again because I feel like such a burden on people
They don't see me sleeping on the sofa when I can barely walk because I'm scared that if there was an emergency in the night, I wouldn't be able to safely get out of the house
They don't see me depressed and hating myself, for something that is completely out of my control
They don't see the times when I'm struggling physically and my entire kitchen side is covered in washing up, when the bin is overflowing, when the floors are filthy, when there's no clean clothes for me to wear. They don't have to live in this mess and hate every second but be unable to do anything about it
They don't see how much I spend on medication, pain relief 'gimmicks' because I'm desperate, additional gas/electric for baths, extra laundry costs and sanitary products because some days I can wet myself multiple times as I can't physically move quick enough to get me to the toilet, on pre-prepared food because I can't manage to stand to cook, taxis when I have gone somewhere and can't propel myself back, additional treatments which probably sound like pampering but when you can't bend your ankles or cut your own nails because your toes are solidly curled under your feet then massage and pedicures become essential
I won't get a promotion at work because I can't be physically present in the office