Getting back to the emotions associated with retiring, or planning for it, and being terrified and all, there is a theory that the process involves consistent, describable stages of emotions, that most people go through, in a way similar to those we have been told exist for dieing.
With death we're told the stages are: denial, anger, bargaining, depression, and acceptance.
According to the article below, there are comparable stages for retiring: planning, excitement, honeymoon, disenchantment, reorientation and stability.
Whether these categories relating to retirement are accepted psychological theory, or merely someone's notions, I can't say, but they're one take on the series of feelings people probably get when facing such a big change as retirement. Maybe worth a read: https://www.actsretirement.org/latest-retirement-news/blog/2019/5/23/the-emotional-stages-of-retirement/#:~:text=the%20emotional%20stages%20of%20retirement.%201%20stage%201%3a,5%20stage%205%3a%20reorientation%20%26%20stability.%20more%20items
But one thing here is for sure. You are going about
this very carefully, doing all the research you need to be doing, and the likely result is that you will have finally chartered a course that will serve you well.
Plus a number of us here are either already retired or, like you, are on the verge of it, so it is also very likely you'll be getting some very good advice here.
Best of luck, and I've got a feeling it will all work out well for you!