Many people who are unfortunate enough to experience such a tragedy as the murder of a loved one, experience guilt and behavior changes.
Here are some examples of those who have lost loved ones to murder, who seemingly have some of the same behaviors / reactions as DT after Somer’s murder; including families restricted by LE from viewing their loved one’s bodies---and who were not guilty---(FYI…these links are to a public website and viewable to all so I didn’t remove the names. They are stories of murder victims provided by members of a murder victims support group and is provided as a resource for others).
http://www.murdervictims.com/voices/Larry_Smith.htm
…L's body could not be viewed; he had lain in that closet in a warm Texas April for nearly three days. He was cremated.
I wasn't allowed to view the body, but was given a lock of hair. I think if I had been allowed to see him, I would not now be subconsciously searching for him, even now, after so many years. To me, somehow, he is not dead...and there is guilt, that somehow if I had not made him leave home, he would still be here where I could take care of him.
http://www.murdervictims.com/Voices/shaline_seguinot.htm (remained unsolved for 7 years )
On August 4, 1995, my 13-year-old daughter SS borrowed a friend's bike to go around the corner and within five minutes she disappeared. Her decomposed body was found three days later, in a wooded area behind the Pyne Poynt School where she attended. S was brutally raped and stabbed to death. When it began, S' mother struggled to accept the tragedy. "S was afraid of the dark. I knew when she didn't come home - I just knew," she said. But for about a year, she didn't believe the body found behind Pyne Poynt was her daughter's. "I kept thinking she was going to knock on the door." S's mother eventually reviewed the autopsy report and its graphic photos. The body had decomposed and could not be visually identified; dental records were needed to confirm it was S. S's Mother was finally convinced by a notation of a scar, on the right side of the victim's face, under the chin. A month after the slaying, she went back to work as a teacher's aide. After a few weeks, she took a leave of absence at her doctor's insistence. The family and church members organized the "SS Fun and Safety Awareness Day" and the "SS Dream Day."
They held fund-raiser after fund-raiser to collect money for a park in S's name. Each event had two purposes: to remember S, and to make sure the investigators didn't forget.
http://www.theatlantic.com/issues/97sep/grief.htm
One might expect that the families of murder victims would be showered with sympathy and support, embraced by their communities. But in reality they are far more likely to feel isolated, fearful, and ashamed, overwhelmed by grief and guilt, angry at the criminal-justice system, and shunned by their old friends.
The grief caused by murder does not follow a predictable course.
It does not neatly unfold in stages. When a person dies after a long illness, his or her family has time to prepare emotionally for the death, to feel an anticipatory grief.
When someone is murdered, the death usually comes without warning. A parent might have breakfast with a child on an ordinary morning -- and then never see or hold or speak to that child again. The period of mourning after a natural death lasts one, two, perhaps three years.
The much more complicated mourning that follows a homicide may be prolonged by the legal system, the attitudes of society, the nature of the crime, and the final disposition of the case. A murder is an unnatural death; no ordinary rules apply. The intense grief experienced by survivors can last four years, five years, a decade, even a lifetime.
The police usually try to shield family members, keeping them away from the crime scene and from gruesome photographs of the victim. Nevertheless, many survivors demand to see these things. They want to confront the reality of the murder and to know the worst. Denied access to the facts by the authorities or by a lack of information about the crime, the relatives of murder victims are frequently tormented by their imaginations and by questions that can never be answered.
Much more at these links if you care to / want to read.