How many of you suspected that Albus Dumbledore and Gellert Grindelwald had a romantic side to their relationship? author JK Rowling, who likes to drop hints for her Fantastic Beasts audience, had earlier revealed that Jude Law's character Dumbledore was in love with Johnny Depp's Grindelwald. However, none of us knew if Grindelwald felt the same about Dumbledore. But we do know that they happened to be great friends who later faced a fallout. Rowling has unveiled the mystery over this big secret now.
“It was passionate, and it was a love relationship. But as happens in any relationship, gay or straight or whatever label we want to put on it, one never knows really what the other person is feeling. You can’t know, you can believe you know," she said in a new segment of the Fantastic Beasts: Crimes of Grindelwald Blu-Ray edition, elaborating the relationship as "incredibly intense". It is to be noted that this is also the first time that Rowling's franchise mentioned a romantic equation.
“So I’m less interested in the sexual side – though I believe there is a sexual dimension to this relationship – than I am in the sense of the emotions they felt for each other, which ultimately is the most fascinating thing about all human relationships,” said the author reports Radio Times.
Potterheads would remember that the two were headed to fight a duel once, in 1945. This happened despite the Fantastic Beasts franchise telling us that the two were committed to not fighting each other. The answer to your 'why then' lies in another edition of the franchise!