About death...

Right after new year, on the 2nd of January, the father of my friend died. He suffered from cancer and gave his last breath in the morning. Due to the situation with his father, she needed some time off and went to visit my place… Words alone could not describe what I am going through after understanding her situation. I feel somewhat weird lately, always seeking for something that is lost… An odd feeling that doesn't seem to vanish from my mind. Have you ever felt like that? And can somebody help me how to console my friend?