"You...realize you're allowed to still feel things, right?" Luke asked after a beat. "There's nothing in the Jedi code that says you have to behave like a droid all the time. And there's no way of avoiding it. Feeling your feelings is perfectly valid. Just know them and don't let them get out of hand." It was just as much a Jedi thing and more a growing up thing, frankly. "Meditate on it and consult the sacred texts if my advice isn't helpful enough -- this isn't a problem I've personally dealt with."
He wasn't trying to be dismissive, but he rather felt that Rey already knew what needed to be done here -- there was no seduction from the dark side here, only some perceived relief from feelings. Which wouldn't be the case anyway. There was a difference in pulling away in order to process one's feelings and keeping dark things a secret forever and Rey was a lot more the latter than the former. He wasn't, if he was being honest with himself, worried about her course.