I've heard it shared that one must be true to oneself. In fact, this sentiment is expressed on one side of many AA anniversary 'coins'. The questions is this, however: which self? The lower self or the higher Self?
I heard it asserted recently that saying 'yes' when you mean 'no' creates an unhealthy conflict because of lack of authenticity. This is predicated, however, on 'what one wants to do' being invariably aligned with God's will. The question for an alcoholic in recovery is not 'what do I want?' but 'what does God want?' If God's will is for me not to do something, then I must absolutely say 'no'. But if God's will is for me to do something, then I must absolutely say 'yes' even when I want to say 'no' and every cell of my being is crying out to say 'no'. This not martyrdom or self-sacrifice, because when self-will is out of alignment with God's will, it is because self-will wants what is not in my best interests. If I remember that God's will always represents what is in my best interests (ultimately and at the level that matters: the spiritual), there never need be conflict, even in the presence of illusions, provided I recall that illusions are what the potentially conflicting thoughts are.