How to cope with murder

Recently found out a woman I knew casually was murdered. She was very kind to me for many years the few times I saw her. Very caring towards my daughter. I am trying to grasp how someone could do such a horrible thing. I can't imagine how other people cope when its someone close to them that they love. I keep thinking about how she was murdered (blunt force trauma to the head) the thing is they haven't released any more details besides thats but its looking like it was possibly her husband who I also knew. They were very kind laid back people and I'm struggling to grasp it. I know when they finally release more information I will probably be able to understand more, but I can't get it out of my head. Like I said I can not even fathom what other people go through when it is a family or a loved one, feeling like there's no closure and needing answers. People who have been down that road are very strong and should be proud of themselves. Any tips with how to cope with murder?