According to Luna Lovegood, here's why Luna and Neville were never a couple
Harry and Ginny. Ron and Hermione. Neville and Luna? In the world of Harry Potter, we kinda wished and hoped that all our favorite characters would couple off in the end. While the first two couples did — and have so far, save a few bumps — and have made their relationships work, Luna Lovegood knows deep down in her heart, she and Neville Longbottom were never meant to be. Even though we shipped them super hard.
Though they never dated in the books, it was subtly implied at the end of Harry Potter and the Deathly Hallows: Part 2 that there was something there that wasn’t there before between them. If that’s a thing that actually happened after the boom/movie ended, and Neville and Luna became a Thing, it never would have lasted. The two of them were simply too different and looking for different things out of their wizarding life.
At the opening of The Wizarding World of Harry Potter at Universal Studios Hollywood, Luna herself, Evanna Lynch, shed some light on this pairing, and explained that even if they had gotten together after the Battle of Hogwarts, they would “definitely not” still be together.
“I think he’s very much a homebody, a stay-at-home dad,” Lynch told Seventeen.com. “And Luna wants to go out and explore the world and different creatures, and I think she wants to have several different relationships and not be committed forever. Neville would want a good sturdy wife who cooks, and that’s not her.”
As Harry Potter legend goes, Neville went off to marry Hannah Abbot and became the Herbology professor at Hogwarts, while Luna married Rolf Scamander, the grandson of Newt Scamander, and the two of them, probably, had some pretty crazy adventures seeking out magical creatures. So while we didn’t see these two favs become Luville, or Nena, or whatever other shipper name we can come up with, at least they both found their own little slice of romantic happiness.