Often the best thing is to express your grief, and this need can be met in different ways, depending on the person, culture and circumstances involved.
It is important to understand that grief is not a sign of weakness or poor coping skills. Rather grief is a healthy and normal part of the healing process to a major life change.
You will change. Your routine will change. Your moods will change. All of this is really about adapting to the loss and changes in your life, your thoughts, your hopes, your beliefs and your future.