When I ask myself this question, I almost want to cry. I used to not think of the Lord so much, even at Mass. That was some time ago. It's easy to spend time doing the many mundane, routine chores. So many hours spent just to maintain the house, the yard, etc., and so much time wasted on watching meaningless TV shows. Those were the hours squandered and lost forever. God just wasn't that important. On a 1-to-10 scale, where do you rate his importance to you? Any number below 10 is doing him injustice.
With his grace, God can draw us close to him and we gradually think of him more and more. Then finally, we enjoy his presence so much that we cannot think of anything else but him. This is fulfillment.