Zexion has always had a rather rigidly structured day since he was a child when his days were dictated by whatever Even was doing and studies. Despite having long outgrown his studies under the eye of Even, Zexion has come to need the structured day. His day tends to follow the same rigid schedule of events. Get up, brush teeth, possibly eat, brush teeth again, shower, go research, fix some books, assist whomever in the basement, possibly eat, write out To-Do list, pass out.
Zexion honestly never thought much about love. While he went from an unstable life to a pretty regular one as Ienzo, he still had long periods of time that he was uncertain what love actually was. He accepted the fatherly love from Ansem, Aeleus, and Even, but was always mostly unaware of any romantic love existing.
Once he became Zexion, he tried to shed any thoughts of any emotions including love. After all, they are heartless beings who cannot feel anything but the strongest emotions.
I will bid all of you a good night, I am going to retreat further into my library and ensure that my pets get fed. Perhaps you would be wise to not disturb me during the night, after all, I cannot control them all of the time.