Thanks for your response, it's good to hear the other side of things.
Would you say that you feel this way because you're the type of person who requires a constant challenge/different aims once you've got what you want or would you pin it entirely to the job itself?
Forgive me if this is a personal question, I'm just trying to sum up both sides because I've always been plagued by the notion that I should keep flying as a hobby or I'll just end up hating it as my job, which in turn sounds like what you're saying.
Any other views?