She spoke at the spring conference of the Association of Mormon Counselors and Psychotherapists on April 1.
Hales said she believes every couple is vulnerable to infidelity -- be it sexual or emotional -- if individuals aren't actively curbing all the subtle and often innocent beginnings of unfaithfulness that can emerge.
"We make the mistake of thinking (marital) vows will keep us safe; and they don't," she said. She also said couples should not depend on love, temple marriage and similarities to keep a couple together. It's not enough. Staying together takes work.
"We are all vulnerable," she said.