Every part of their lives is affected. Some can't hold jobs, and families break apart. Grieving parents may not realize their own children are also suffering. They often develop mental and physical health problems, including eating disorders, insomnia, depression and paranoia. They get pain in the arm or chest, where their loved one was shot. In a phenomenon known as "broken heart syndrome," intense grief can weaken the heart and lead to heart attacks. So can the anger, scientists say. In certain cases, some researchers believe, the burden of grief -- if not treated -- can kill people.