I teach, so I have nothing in the way of advice to offer you, as I know absolutely nothing of the corporate world (thank goodness). I DO KNOW, however, what it's like to hate your job. I left my last school after 9 years because my attitude got increasingly worse over the last couple years. I still loved the kids (although they were becoming increasingly spoiled and bratty because of their parent's attitudes), but hated administration and their ridiculous demands on us (it was a private school). I even considered leaving teaching altogether and interviewed at many corporate companies. In the end, I simply changed school districts, and although I can no longer feasibly commute by bike (52 miles/day), I am much happier and peaceful. I like my job again and don't dread going in to work.

I'm with your hairdresser. Find something that makes you happy. Money is important, but your sanity and peace of mind is more so. You'll get by just fine (and if you really do sell your car and go car-less you could even look for a salary a bit below where you're at now).
Look into other jobs and see if something else is out there for you. Your happy job is out there somewhere... Good luck, Yellow!