I don't think anything could be further from the truth. That they cannot connect is what makes them two dimensional. This isn't like George Clooney and Michele Pfieffer hugging in a fountain, with money to spare and their only problems in life being unable to time things right. For example, Fai shows up at Wing's drunk and ready to kill him. But behind this is the love and fear that he feels as he sees Wing at his lowest.
Wing is a fickle person.
He wants love, but he doesn't want to be tied down. Fai is passive aggressive. He likes being the disciplinarian and likes to complain. He'd rather lay down the law then forget about things, rather have the truth than love. Fai says he was happiest with Wing when Wing's hands were broken and asleep.