I'm going to let the novels do the talking.
Both Darcy and Edward are set apart by their emotional distance.
When Edward and Darcy declare themselves, it is phrased like surrender. Darcy says, "In vain have I struggled. It will not do. My feelings will not be repressed. You must allow me to tell you how ardently I admire and love you." Edward tells Bella, "I'm tired of trying to stay away from you," and "You are the most important thing to me now..." (Twilight, 85,273.)