What does this quote mean the vitality of his illusion had gone beyond Daisy everything in Great Gadsby?

This quote from The Great Gatsby suggests that Jay Gatsby's obsessive pursuit of Daisy Buchanan has become more potent than his feelings for her. His vision of her has surpassed reality and become a distorted fantasy that drives his actions and motivations. This illusory ideal of Daisy has taken precedence over everything else in his life, including his own well-being and sense of self.