Synonyms for Withdrawal (same or very similar meaning)
WordNet sense 1 (avoiding emotional involvement):
detachmentWordNet sense 2 (a retraction of a previously held position):
backdown, climb-downWordNet sense 3 (formal separation from an alliance or federation):
secessionWordNet sense 4 (the termination of drug taking):
drug withdrawalFrom the ODE community, based on WordNetadd/edit