Apologies to all for leaving this thread for a long time... Busy times!
Feeling very slightly better, though I don't know if I could get on an airliner still.
The most comforting reply so far was tom775257's:
I would suggest that a structural failure casing rapid depressurisation would be a very unlikely scenario. A much more common (but still VERY rare) cause of depressurisation on the type I fly (I suspect on others too) would be a slow depressurisation due to dual air bleed failure (air taken off the engines) or dual pack failure (aircon units). Generally it starts with an innocuous single failure, but the extra stress due to becoming the single source can sometimes send the other one into failure too. Now the aircraft will drive its outflow valve shut (where air from the cabin is exhausted) but now you are relying on seals to keep the pressurised air in the cabin.
The good thing about this scenario is you can beat the cabin down, so emergency descent circa 6000' per minute, the cabin climbs about 1500' per minute depending on the seals etc. on the aircraft. Generally you can get the aircraft below 10,000' (MSA depending) before the cabin hits 14,000. Not too bad on the ears, no fog, no masks for the pax. Also with dual bleed failures, we can get the APU lit in the descent and get some bleed air off that at 20,000' and restore normal ops.
A full on proper depressurisation is a well practiced procedure, sure you might blow the odd eardrum of someone with a bad cold, but it isn't going to kill you. A pilot friend of mine burst an eardrum flying, first thing she knew about it was a bit of blood out of her ear, not particularly painful for her apparently.
Don't ask me why, I just found some comfort in that response. Maybe I should do the ATPL exams (or at least get some books), perhaps it's the knowledge gained from the PPL creating uncertainties and to some extent unnecessary thinking when it comes to airliners.
Strangely, it appears I don't find statistics comforting. I somehow have it in my head that failures in a car or at low ish level in a light a/c are less likely to kill me than a failure at 450kt on the edge of the atmoshpere.
I wonder how numbers compare when looking at, for example, the percentage of failures or met events resulting in death or injury in a light a/c compared with the percentage of failures or met events resulting in death or injury on an airliner, including and excluding pilot error in both percentages.
Thanks for the replies, much appreciated. It seems I may in fact be the only one confident in light aircraft whilst being scared of an airliner! Luckily I'm not due to travel any time soon.