Ironically, the perfect word to end that sentence rhyming with “here” was right in front of my eyes the whole time.
“Pushing Ben toward that throne was my greatest fear. What are you most afraid of?”
Again, this line helps to rationalize Luke’s decision to isolate himself on Ahch-To. It’s not just about running away from his failure, it’s a calculated decision to prevent further harm to his nephew, the Force itself, and the galaxy at large. Luke once believed that his light’s proximity to those with potential for the dark side might inadvertently push them toward the lost Sith throne. The Jedi code being awful was just another contributing factor for it all, but Luke is finally able to summarize the heart of his previous issue here.