I was a lecturer in chemistry for 16 years. When I started, I felt it was the best job in the world, but towards the end, the changes in university education system made me very glad I had a way out.
Luckily, my partner and I started our own software company, and we both still work together in IT, and still in a small company. However, we didn't just leave our secure jobs on a whim - I had been writing and selling software, part-time, at nights and weekends for ten years. Finally, that paid off - our company, based in a bedroom, made two enormous corporate sales which gave us the capital and confidence to go at it full time.
That's just my story; I know of others who simply went and got jobs in areas that were only vaguely related to their academic career and made a great success of their new career.
It's often a difficult choice, especially as an academic career is pretty safe, but there's no harm in exploring options and sometimes in life you have to take a leap into the unknown to get where you want.
Whatever, I'll state the obvious by saying you need a definite plan and to list the pros and cons before acting - sometimes, your current situation isn't as bad as you think!
(That all said, my partner and I are actively planning to embark on a completely different business within the next year...)
Good luck!