Antipathy and aversion are closer synonyms than their corresponding adjectives when they denote the state of mind created by what is antipathetic to one.
Antipathy distinctly implies an emotional state, often a settled emotion, which prevents reconciliation or contact or which more often definitely implies hostility (see ENMITY).
Aversion on the other hand suggests a predisposition or an unwillingness to meet, encounter, or entertain, which shows itself in avoidance or rejection rather than in hatred; thus, one has an antipathy to cats who is violently repelled by them and drives them from his presence; one has an aversion to cats who merely avoids contact with them.