A disability worthy of more attention?....

Today,
Sitting on the bus, coming home from school, a man in a wheel chair boards the bus. The process is long and arduous for all and it feels like most of all for those observing. I see faces wrought with concern and agony, almost more embarrassed for themselves having to witness this, than for the man doing what he probably goes through each and every day. Nothing out of the ordinary, although still probably exacting its toll on him just same, but for us a sudden wave of concern and shame at our unwillingness and shyness at offering some help or aid.
All the reason we should feel guilty for not doing everything in our power to make this person feel comfortable and welcome in our midst, instead of awkward and embarrassed for taking up so much of our precious time as he boards the bus. Then later, sitting outside the Laundromat as I read A New Kind of Christian by Brian McLaren, I glance up to see a woman, looking every bit the same as any other, limping up the street. As I feel my on cue emotions of sadness and pity for this person that's been so hard done by, it dawns on me. Why do we feel so much discomfort and sadness towards people who are physically disabled, when they themselves often adapt and function very well over time. Is it that we, as a society, value and worship the physical so much, that we find a limp, or the inability to walk, the most catastrophic affliction that one could suffer?
I feel no such feelings towards those I know or have met who suffer from A.D.D., Schizophrenia, bipolar, borderline, O.C.D., autism, or a learning disability. Further more, I wonder why we feel compelled to attach the word suffer on to these titles, and yet don't feel the same sadness for them as for someone who is disabled. Don't we all suffer every day. Arthritis, migraines, food allergies, asthma, are all so common, yet not considered nearly as horrible as someone who was born missing a leg or an arm. It seems to me that perhaps our society covets the physical being and almost brushes the mental off as being unimportant.
I've also noticed that throughout this posting I have used the term "we" when really explaining my own perceptions and feelings. This is likely not fair as there are people out there, no doubt, that feel as much sympathy for someone with a mental disorder as for someone in a wheel chair. Perhaps it is merely myself that needs to work on reversing my perception of what are really the most important things in life.