Maybe it's time to refresh your motivation. In Zen, there is an interesting concept called "Beginner's Mind." The goal is to maintain the wide-eyed willingness and spirit of a beginner, even when you have gained much experience.

What were your motivations and expectations when you started having success? And what are your motivations and expectations lately? Sometimes our goals become dull and generic. It's not enough to just say "I want to have lucid dreams." You need something specific and visceral to motivate you, like "I want to feel the rush of wind as I fly over New York City and look down on the skyscrapers."