Instead of feeling guilty about neglecting it, admit that you can walk away for a time. Poof! guilt gone and free time ahead.
I appreciate that, Commodore. Although I wouldn't exactly call this "burnout" when I never needed to do this in the first place. Sometimes, having little to prove is worse than having everything to prove: You assume a "why bother?" sentiment which hurts your motivation.
No, in case you're wondering; I haven't won the lottery. But I definitely ain't suffering either.
I guess I'll follow the advice of Maria Ross from Fullmetal Alchemist: Proceed with your goals, but without obsession of what the final outcome will be.