Sudden versus Predictable Loss
Sudden or shocking losses--due to events like crimes, accidents, or suicide--can be traumatic. There is no way to prepare. They can challenge your sense of security and confidence in the predictability of life. You may experience symptoms such as sleep disturbance, nightmares, distressing thoughts, social isolation, or severe anxiety.

Predictable losses--like those due to terminal illness--sometimes allow more time to prepare for the loss. However, they create two layers of grief: the grief related to the anticipation of the loss and the grief related to the final loss.

I myself have experienced both. The pain is just as strong in both I think. I feel the biggest difference is that in predictable we have time to say the things we need to say to the loved one. To me that means so much.