Yesterday I found that my position was affirmed by the authors of a new book I will be using for optional reading in the course next fall, Self-Esteem by Matthew McKay & Patrick Fanning. Here's what they say about ethics and psychological well-being.
Healthy values are realistic. This means that they are based on as assessment of positive versus negative consequences. A realistic value or rule promotes behavior that leads to positive outcomes. It encourages you to do things that result in long-term happiness for the people involved. That's the purpose of a value. You follow it because in your experience the value guides you toward a way of living that feels good. Unrealistic values and shoulds have nothing to do with outcomes. They are absolute and global. They prescribe behavior because it is "right" and "good," not because it leads to positive consequences. Unrealistic values require you to act "on principle," no matter how much pain the act brings to yourself and others.
In the study of ethics, this approach is called consequentialism. What makes consequentialism appealing is that ethical systems based on absolute principles inevitably reach a point where some of the principles contradict each other. This problem can be demonstrated on a very simple level. Consider the conflict a child must face when trying to decide whether the highest good is telling his parents the truth or keeping a confidence with his brother. He will have to break one of his principles by either lying or betraying a sibling. The only realistic way you can escape such an ethical quandary is to evaluate the negative and positive consequences of each choice for all parties concerned.