"until Blair & Brown destroyed the country"
Glad to see your Daily Mail subscription was worth it
On a more serious note, I would agree with those who say it might be a lot to do with how you treat your job.
I had two careers prior to aviation and I can vouch you're unlikely to be happier with an office job. Try spending half your day looking at pointless PowerPoint presentations and the other half listening to your MBA boss regurgitating one cliche expression after another. Once home, your evenings and weekends will be punctuated by Blackberry emails sent by ladder climbers who want to be seen working during home time. And you better reply. You think you have to cope with bull**** now?
I'm not saying don't quit. Maybe it's the right thing for you. But if you do, I would advise starting your own business...
If you can, go part-time and do something like instructing, para-dropping, etc. In other words, remember why you started flying in the first place. It's not the job it used to be (based on the accounts of old timers). But trust me, it's far better than most jobs out there...