I retired 10 years ago at age 58 because I was a victim of The Peter Principle, the stress was getting to me, I hated to go to work. Coincidently a severance was offered and I was free. The only advise I can give is stay busy, boredom is the enemy of a healthy attitude.
I ride, volunteer at my local Yellow Bike , travel to see grandkids and stay out of my wife's way. There are other things but you get the idea.