Sounds like your affection isn't high enough. Check out the affection part of the guide for the choices that raise affection or replay with the affectionate trait (gained from the going back to normal end).
There are tabs at the bottom for navigation. The one for Zane specifically is:
https://docs.google.com/spreadsheets/d/1CjKGkKfTB3aXmScImrjptJ_K2RbyADv-1aB_B5uN...
If you scroll to the bottom of the tab you can also see the amount of affection required for each end.