It sounds like mid life crisis time. No? From your postings on this site and your blog, it is no wonder you feel burned out. It seems you are constantly on the go. Even being able to travel en femme and "relax" in a hotel room does not replace kicking back and relaxing in your own home. At forty-seven I had to be still employed. I had kids in college and high school, and, a wife planning on getting her degree. The job I had for thirty plus was very confrontational. I was burned out for decades, but, I had to keep going. In my line of employment I reached the **** You date, when management could fire me without any adverse consequences. That made life tolerable until I was ready to pick my time.
I can only tell anyone who cares to listen you need to be debt free, live within your income, and, have realistic expectations. A person must control his destiny. If you rely on the government, then you're sunk. With defined benefit retirement plans gone, Medicare eligibility at 65 or 67, full social security retirement at 66 or later, most people are going to feel really tired for a long time.
What a lot of people do is to bag their current jobs when fully vested in a retirement plan and take their expertise to a less stressful and a new direction. Have math and engineering skills? Try teaching at a trade school or college.
And, if you really like what your doing, don't retire!