I look forward to 75% of my training sessions. I love deadlift and max effort days. Setting new PR's in lifts is a measurable goal, so I focus on that. I also have specific bodyweight goals in mind. The other 25% of the time, I may not be uber geeked about going to the gym, but once I get there, I find my rhythm.
I think you need specific goals in mind. Set short, medium, and long-range goals. That's what keeps me fired up!