I made the mistake on someone else's thread to suggest that THIS resulted in different issues for those of us who married their HS sweethearts----for those of us that didn't have a life before their H. I was quickly shot down for thinking such a thing. So, I guess it's just me.
I think you have a point there! I read so much similarity in sitches like yours, and Treese's and a few others.... I think it is a valid concern. I don't think it is just you.
I think your analysis of your "problem" is spot on, though! You need to find out who you are, and what you want. The trick is figuring that out, isn't it? I think you've made a start, though. I think the walks, and things like the gym will help. I thin kthey clear your mind, and may let it go places that it can't go when you try to direct it. It may well be during those times that something important comes into your head. The other thing that night help is to purposely do things that you might not have done, or thought you didn't like. Go to a movie by yourself. Or even rent a movie you never thought you'd like. Try to move yourself "out of the box". Experience things you haven't, see if you can learn something about yourself.
If you have the means, travel a little, even weekend trips. See places you haven't, maybe even in your own area.