I retired from teaching at 61, as did DH, but straightaway he started a different job, for five years, meant to be part time but he made it full time. So all the things I hoped we would enjoy together did not happen, and now 15 years on, we have aged too much.
I filled my time with voluntary work, church, choirs and grandchildren, a good balance. I do less on all fronts now, but enough to keep me busy, though I still have lots of time to myself which I admit to spending online. I do get bored and lonely, even though I have several points in the week where I interact with others in real life.
I guess the point Iwant to make is it depends what sort of person you are and what you want to do. Sitting on the patio reading will probably not be enough for you for very long, even with trips to the coast. It is not just whether you can afford it financially. A lot is said about mental health, but think what makes you tick, what energises and stimulates you. Have a plan, don’t just drift into retirement because you can afford not to work.