- faithlessness, falseness, fickleness, inconstancy - unfaithfulness by virtue of being unreliable or treacherous
--1 is a kind of infidelity, unfaithfulness
- inconstancy, changefulness - the quality of being changeable and variable
--2 is a kind of changeableness, changeability
Antonyms: constancy, stability
--2 has particulars: capriciousness, unpredictability