It's not so easy for me to do a career change. I'm a physician, so I have 4 years of college, plus 4 years of medical school, plus 3 years of residency in learning my trade, that cost me a LOT of money. It would be very difficult to find a new career that would match my salary I'm now accustomed to. I do realize this is a good problem to have, FWIW. If I did find a new career that I enjoyed, I think it would likely cause me to work many more years, and even if I did that, I'd still be a slave to the clock...
I have been moving more into administration at my job. I'm now the associate medical director of a large FQHC. This has been a nice change of pace, and has cut down my patient contact hours. However, it has actually added a bit more stress many days.
Ultimately, I don't hate my job, but I am getting burnt out... It's the demanding patients that really take it out of me. 5% of my patients cause 75% of my stress, unfortunately. The other 25% is the administrative/paperwork burden.