There's another option: you can learn to love what you do, or at least like it more. A typically western mindset is that if you're at point X and you want to be at point Y, the route to happiness is moving from X to Y. Simple enough, in theory, and this essay provides a lot of insight on how to achieve that, where Y = a career you love.

On the other hand, though the idea may be foreign to a lot of us, you can learn to want X. It requires something of a massive paradigm shift and requires plenty of work that resembles various eastern practices such as Buddhism/Yoga. There's an excellent book on the subject by Timothy Ray Miller called "How to Want What You Have:"

http://www.amazon.com/How-Want-What-You-Have/dp/0380726823

edited to add: I should note that these approaches aren't neccessarily in conflict. You can work to do what you love, or if for whatever reason you can't, you can work to alter your mindset to make what you do more interesting.