1) Grief and loss are universal human experiences that can be triggered by separation from loved ones, failure, or life changes that disrupt familiar patterns.
2) There are various types of loss including actual, perceived, physical, physiological, and anticipatory. Key factors that influence grief reactions include the significance of the loss, culture, spiritual beliefs, sex role, socioeconomic status, and coping skills.
3) Common grief responses include shock, denial, anger, bargaining, depression, and acceptance based on Kubler-Ross' stage theory of grief. Other theorists like Engle and Bowlby proposed similar stage models with numbness, yearning, disorganization, and reorganization.