Sorry for your loss, and know how you feel still. I have lost three brothers at young ages, one while I was recovering from my own treatment, and not a day goes by that I don't think of them. It takes time to and how long, is different for anyone. There are phases one has to go, each taking its own amount of time, to finally accept this loss. These are shock, sympathy, blame, anger, depression and finally acceptance. Maybe seek bereavement counseling, a friend or support group to help you.