It is hard to remember that those who have experienced the same situation of loss, those who were together through all the minutes of the days and who share the experience of the same grief experience their grieving in isolation.
We grieve as individuals, even though we sometimes do that together.
Having gone through a similar circumstance, even the same circumstance, can provide empathy and even community.
But it does not mean we know how others are grieving. Each grief is its own process, each mourner is unique.
Even if we gather to mark the loss each needs the space to experience their unique loss, and not be required to be experiencing it the way that others are.
I have been daily grateful for the friend who remarked that grief isolates. He di not mean that I, grieving, am isolated from you, happy. He meant also that shared grief isolates the sharers from each other. Though united in that we are grieving, we grieve differently. As each death has its own character, so too each grief over a death has its own character – its own inscape. The dynamics of each person’s sorrow must be allowed to work themselves out without judgment. I may find it strange that you should be tearful today but dry-eyed yesterday when my tears were yesterday. But my sorrow is not your sorrow.
There’s something more: I must struggle so hard to regain life that I cannot reach out to you. Nor you to me. It’s when people are happy they say, “Let’s get together.”Nicholas Wolterstorff, Lament For A Son, Spire 1989, pg. 56
mgpcpastor's blog 
Very true and very helpful.