If you just try long enough and hard enough, you can always manage to boot yourself in the posterior.
All species capable of grasping this fact manage better in the struggle for existence than those which rely upon their own strength alone: the wolf, which hunts in a pack, has a greater chance of survival than the lion, which hunts alone.
Grief is never something you get over. You don't wake up one morning and say, 'I've conquered that; now I'm moving on.' It's something that walks beside you every day. And if you can learn how to manage it and honour the person that you miss, you can take something that is incredibly sad and have some form of positivity.