I get that too. A couple of things that have helped me with that are a version of "Getting Things Done" (gets tasks out of my mind) and genuine solitude. By that I mean don't read anything, watch anything, etc. No inputs, just your own mind. Just sit there and zone out a little. Nudge your mind with reflective thoughts like, "What's important to me? What do I want out of life? How do I feel lately?" Meditation emphasizes stepping back and not putting judgment on things like that, which I think can be healthy, but this is kind of the other side of the coin and helps get a little more of that closure you're talking about.