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The recent murder cases of Annie Le at Yale, possibly by 24-year-old Yale lab technician Raymond Clark, and of Trisha Leffler by accused Craigslist killer Philip Markoff obviously took the lives of two young women and shattered the lives of their families. I have treated parents of murdered children, as well as their siblings, and know that the surface scars may fade over time, but that the internal emotional bleeding-the complicated grief-never seems to end.

Less attention is paid to the other victims of such horrific crimes-the families, girlfriends and friends of the killers. Both Raymond Clark and Philip Markoff were not only the sons of mothers and fathers, but both men were engaged to be married. In both cases, if convictions are obtained, their fiances are left to pick up the pieces of their psyches, battered by the knowledge that they had loved and committed themselves to men who were pathologically violent.

When one's son or daughter, husband or wife, or fiance turns out to be a stranger full of darkness, it is a reckoning with reality like few others. I have counseled such individuals and seen the tears in their eyes and the stress in their faces as they tried to make sense of how someone seemingly so close to them could have been, in fact, infinitely far removed. If people who profess their love can keep their darkest truths under wraps, who and what can be trusted in the world?

Many, many people know something about the challenges that face the "survivors" of intimate connections with murderers. After all, my practice has long been populated by those who were injured by assailants who played the role of parents, teachers and mentors. Their ability to trust is often long in being reborn, relying not a little bit on how trustworthy and reliable I can be as a clinician. Such is the miracle of human empathy_ the example of a decent, caring relationship can mend some of the damage done by a harmful one, even a predatory one.

Yet to have lived with or loved a killer is a special case. The journey back from that kind of terror and self-doubt has several ingredients. First, it has to be said that there are among us men (and women) who can indeed wear what the great psychiatrist Hervey Cleckley called a mask of sanity. Having buried their destructiveness and rage deep inside them (until it explodes) they become people imitating people, doing those things that seem kind and respectful, without feeling kind or respectful. They are playacting, and they can be better at it than the best actor in any movie. Scott Peterson, who killed his wife Laci and their unborn son Conner, was such a man-likeable, with good manners, able to win women over with one-liners harvested from movies and chilled champagne tucked in a backpack for a romantic hike.

So those who share their lives with killers can take some solace in the fact that many pass themselves off as normal, even to law enforcement officials and psychiatrists. That's the easy part.

The harder part is understanding that there can be a reason why those who turn out to have loved killers find themselves in that rare psychological territory. And often that relates to their own willingness to distance themselves from core feelings of anger and anxiety and accept the surface of things. Very often the lovers and best friends and even parents of killers have had traumatic life experiences that paved the way for them turning a blind eye to their emotions and instincts, making them the ideal partners for predators.

Predators can sense when they are in the presence of others who will take them at their word.

Like most of our emotional challenges in life, the biggest hurdle to healing for those with a killer in the family is looking inside themselves, at the very things they have tried to avoid seeing.

Dr. Keith Ablow is a psychiatry correspondent for FOX News Channel and a New York Times bestselling author. His book, "Living the Truth: Transform Your Life through the Power of Insight and Honesty" has launched a new self-help movement including