I was the same, not too appreciative of others situations, until I ended up in hospital with multiple fractures.. some in my lower spine.
That was 37 years ago, and having spent much time in a wheelchair while in hospital for 3 years, then 18 months on crutches while in various body casts, I am only too aware of how tough people do it when confined to a wheelchair and or walking aid.... and just how rude some people can be because you are not as mobile as they are and therefore slow them down/inadvertently get in their way. Oh, and ask someone to pass something you can't reach because yo can't stand... some are just plain ignorant, and others make out you've just asked them to pass down the entire shelf and 3 quarters of the contents of the store's distributing warehouse as well.
I went back to work after that and did some heavy duty stuff at that, like road building (the old fashioned way, manually), railway track maintenance (again the old fashioned manual way) and furniture removalist... mover to the uneducated, but my old injuries got the better of me eventually and I had to retire due to those and other health issues.
I'm not in a wheelchair as yet, and I don't use walking aids, either. I dunno, probably because I'm a stubborn old bastard, but I am of the opinion that if I can still walk I should. I can't walk great distances [shoot, not even moderately short ones some days] but I will not succumb to being totally incapacitated and riding in a wheelchair until the absolute last thing... when I CAN'T walk.
Much of that determination, I think, goes back to when I was confined to a wheelchair and some of the impatience and rudeness I encountered at times. In this bustling day and age of people wanting to be there yesterday, the rudeness and impatience seems to be worse than yesteryear, so naturally I want to avoid that as much as possible. The other advantage to being on my feet, say, in a supermarket, etc... when somebody bitches and abuses me for being so slow, I can turn around intimidatingly [@ 6' 2"] and say "well fuck you too". Hehe!!!! In a wheelchair that ain't so impressive... or intimidating, so I ain't gonna depend on one of those for yonks to come if I have my way.... cos I still wanna say "eff you" and not get spun around in one 'til I'm dizzy
I can hardly sit at my pc to get anything done...if I stand to long both my upper legs go numb and then my back feels like its going to snap in half. I spend most of my time lying in bed because I've yet to find any pain meds that do anything for me. All I can tell ya is that it's bad enough that I won't tolerate it for long if these doctors don't come up with something soon. Not a good thought but there it is.
We make a fine pair, don't we WG, and not being able to afford that busty blonde nurse doesn't help any, either. I've applied for a supplement to my DSP [disability pension] to be able to afford one, but the pencil pushers behind the counter say I need to be much shorter and 10kg heavier before that happens. I can see how that would be to my advantage... being eye-level with the cleavage, but c'mon.... I WANT one NOW!!!!
Seriously, mate, we are in very similar boats and I'm only too aware of how you feel. I too spend quite a bit of time laying down, but moreso for vertigo/travel sick issues that often dog my days. I have an inoperable spinal condition in my neck that causes this, and while travel sick pills help to some degree, they don't always provide the relief I need to get on with my day. Yup, the pain is excruciating at times, and then there is no... well, very little walking due to numbness and pins n' needles, etc, but I still won't roll over and get a wheelchair. Nope, for me that's the beginning of the end, so hopefully it's a few years off yet.
I am fortunate in that I have a great doctor and can get fairly decent and affordable pain relief medication these days, otherwise I don't know how I'd cope this well. The pain threshold is sometimes more than I can bear, however, but for the most part it is manageable and I am sort of functional. I know how chronic pain can be debilitating and cause depression, so hopefully you too can access affordable and effective medication to improve your circumstances. I know what you're saying and why, but please hang in there, mate, please hang in there....
... you're in my thoughts. 
