This I know: Some folks can look healthy as a horse and still be disabled, For example there were two periods in my own life where I could only walk a short distance.. The distance from my RV to the laundry room in the park, for example.. I had to sit down half way and rest a while (Thankfully that one only lasted about a week.. And I know the cause (I had just gotten out of hospital where I spent a week) 2 weeks later at a follow up Doctor's appointment I parked the car at the hospital and checked into the cafiteria for some brunch and Wi-Fi (bad but better than park) and when it came time for lunch and the Cafiteria filled up I checked out and walked the half mile to the Doctor's instead of driving.. kind of impressed the doc it did. nice walk, Decent weather, Cool but not cold,, I like that time of year.
And back around 1998 I had bad neuropathy (Still do but it's settled down) and walking was PAINFUL. Again, I had to break up long walks.. When shopping a "Super store" (THink Wal*Mart though i tend to avoid them there are others). I'd pick up the first loose shopping cart in the lot and use is as a "Walker".. i still do, only now it is for a different reason (Courtesy, saves the store picking it up).
but through all this I look healthy, no cane, no cast, no wheelchair.
A friend of mine,, often could run around almost as good as a child,, Those were his good days.
His bad days.. He could not walk at all.
HOW TO TELL if someone is really handicapped:
The truly handicapped come in two types: Some are handicapped all the time, Example is someone in a chair.. They may use handicapped license plates. but the ambulatory handicapped who have good and bad days.. They use hang tags.
On a good day the hang tag goes in the glove box and they save the handicapped site for those who need it.
On a bad day.. They need it.
Sounds like the Original Poster is that kind.. on a good day the hang tag does not hang. on a bad day they need it.
Now... Those who are not really handicapped: I know one woman who's mother qualified as Disabled (And for good reason I might add) She would take her mother shopping and such, so she had the hang tag in her car, she would use it even when she did NOT have her mother with her. Even though she was more mobile than I am... She used a scooter in the campground, Even though I walk and she is less handicapped than I am (Well on a bad day I take the bicycle cause i can ride when I can not walk.. Yes, i understand why, plus I kind of like riding the bike).