Looking for a happy empty nester book!

Please suggest a book with a FMC who is 40+, an empty nester or becoming one… and then structures her life with lots of alone time and freedom. Maybe she does a long distance hike, maybe she buys a cabin in the woods. But her post-kids life is not about her career, her husband or desperately clinging to/ meddling with/ ”fixing” her children. She has healthy relationships but no longer centers them… she goes on a journey involving much solitude, nature, and self-love.

Anything? Anything even in the ballpark of that would be great.

TLDR; book about “healthy woman, 40+ yo, de-centering relationships, loving nature”