Lady Grey, I can relate to your retirement transition challenge. It's a problem most people face sooner or later, and for those of us that had exceptionally fun, interesting, or satisfying carers, it's tough to give it all up. My own brother lived solely for work and would never have given it up if he hadn't got cut at age 71.
Some people have or find a new purpose in life to fill the gap of their lost careers, but most like you don't. They may spend a few years catching up on house projects, traveling, or playing more golf, but few actually pursue a genuine, satisfying purpose for their life. Doing chores, having a daily routine, and staying busy may accommodate a tolerable adjustment, but it's not a satisfying solution. We need more.
Now, there are several purposes in life to pursue once one retires and has more free time. One can return to a different kind of work to make money, get social interaction, and feel some sense of value and productivity. Half of my retired friends have done this - having new post career jobs. It's a viable option, but since none of them actually need the money, I think volunteering - giving back to society - is a more worthy cause. The need is infinite and a senior's volunteer time so valued. Now that's an avenue for regaining a sense of work satisfaction back.
In my case, I've used retirement freedom to not only travel the world full-time, but to focus on my faith. Though I've been a life-long Christian, most of 35 years was dedicated to my career, and losing that has forced me to find a new purpose in life. With time and effort, I've turned my part time, passive faith into a full time, active one. The result has been life changing, giving me an ultimate purpose and joy for each new day and hope for the future.
I believe that having a close relationship with our Creator is the most important thing in life. It's why we exist. As we grow old, leave our careers behind, and become less enamored with worldly pleasures, our real purpose in life never changes. But as a retiree, it's nice having more time, wisdom, and incentive perhaps, to become passionate about it. There's so much to learn and do as a Christian to make use of the time we've been given here. Just being busy is not the goal, nor will it yield satisfaction. There needs to be purpose, and there's no higher one than knowing and loving God more each day, and showing love and care for others.