Given all you've done, I know you can do this. Put yourself in group two.
I've always imagined there to be three groups of people for anything that gets accomplished, whether audacious or mundane.
Group one are those who accomplish their goal. Group three are those who think about setting a goal or doing something, but never take action towards it. And group two are those who believe in themselves enough to give themselves a chance at reaching group one, they take action towards their goal.
Put yourself in group two. Sometimes, something or someone outside your control helps you see that group two is possible in whatever you're pursuing.
I'm here to say that you don't have to wait on someone else, put yourself in group two.
Whether you want to write a book, join a club, run a 5k, or do anything else, put yourself in group two. Give yourself the chance. It's amazing what we can accomplish when we do.