That is, his one desire that was for Lan Xichen couldn’t be shown to anyone, not even Lan Xichen. So Lan Xichen felt it was one-sided, but he keeps questioning if it really is, but he’s too protective of their friendship to break it, and thus never confesses and never confirms jiggy’s suspicions

He was bi (headcanon), and when he met Lan Xichen, he very much fell in love but hid it because he had to be the perfect son to be recognized by Jin Guangshan (even though we as the audience knew he could have been perfect and his dear ol’ dad still would have hated him) but this one “imperfection”