Board Thread:Questions and Answers/@comment-33751959-20171124105437/@comment-2001:558:6027:4:7D52:6334:8A44:8580-20171125151735

There is But One Ultimate Way isn't canon, Reki has confirmed this on his Twitter and he wrote it as a form of satire towards the harem genre because he himself hates harem; he is a devout Kirisuna shipper as he has called them the model of true love and even soft-retconned the details of their first meeting in Progressive so that they could meet and travel together from the beginning of the series instead of the year and a half into SAO like the original(professing that he can't see Kirito without Asuna by his side). He also stated that the series will end with their wedding. As for why Asuna doesn't get jealous, it's because she knows that he is loyal only to her and their mutual female  friends respect hers and Kirito's feelings, which is why they don't interfere in their relationship. That's also why Kirito's never said anything about their  romantic interest in him because they aren't actively pursuing/competing for him.

Alice is the only girl who tried to stake some claim on Kirito and when that happened, Asuna got pissed and bluntly told her that Kirito was hers. Ironically, Alice is the only one who doesn't have a romantic interest in Kirito, she simply has a deep respect for him as a warrior and became  protective of him while acting as his caretaker when he was catatonic for months(which didn't sit well with Asuna because she views herself as Kirito's protector and battle partner). Meanwhile, Kirito has never once entertained any romantic attraction with any of  the girls outside of Asuna. In fact,  he even apologized when he gave an innocent kiss to the forehead to a little girl for her gift, mentally asking Yui and Asuna to forgive him. So yeah, he's not cheating on Asuna nor are his feelings shifting. He's every bit as loyal to her as she is to him.