Death is something we all face. We as human beings never will truly know our own fate. Tragedies like this are avoidable but fate decided. We always think to ourselves "it happened to somebody else". It doesn't make it any easier to cope with especially if it is family and friends we lose.
I personally have lost a lot of good people in my journey through life. I am not an old man but those passings aged me considerably...My grandfather, my father, my elder brother, my favorite Uncle, my best friend growing up and two of my beautiful cats. Their deaths took a piece of me away and now I am a soul that has many holes that cannot be filled. I surprise myself by waking up everyday and continuing on my journey. My road gets tougher as I go but I'm still going.
I sympathize with your loss and understand fully what you must have to endure to keep moving forward.
It may not mean much coming from a stranger but you will get through this...continue your journey and make sure you always take the time to honour their passing by living your life to the fullest. As long as you remain, their memories and lives do too.