There were many times where I thought I’d never make it to retirement. I’m still amazed I did.
If I might offer one recommendation- Have a plan for what you do next and lay the groundwork for that plan ahead of time. It doesn’t need to be complicated or expensive but definitely have a plan. Lots of guys I worked with never had a plan and paid the price- or their plan was: not working and that’s it.
Every human needs social, mental, and physical stimulus at a minimum to be healthy and if you don’t get those things in your retirement you’ll be in big trouble.