I was too naive to think that getting my dissertation out of the door would help with this. Unfortunately thinking about my research projects (either tweaking the old ones or starting new ones) still got me all excited and stay wide awake for a couple hours in the middle of the night. It was fun but I am really tired now.
So I guess there's no escape; I let go of my other dreams when I graduated from the college and chose the path to a research scientist. There were some tough times and I can foresee more challenges are yet to come, but all in all I think I made a good choice. I should be grateful for how well things turned out.
This reminded me of a career development talk I went to awhile ago. The speaker (sorry I forgot his name, maybe I should try to find this in my emails) said that the main point is to have fun and not thinking about scientific achievement, fame, or money. He used the big biochemical pathway diagram as an example; every tiny arrow on the map was the collective work of many scientists' lifetime achievement and still subject to revision. Very few people can make the quantum leaps in our knowledge, the majority of scientists are more like worker ants in the colony. Compared to other professions with similar training requirements, the pay for scientists really isn't that great. So if it's not fun, you would be better off doing something else. I guess he got a good point and I am glad about where I am now.