I remember coming across a youtube video once upon a time, which explained grief/trauma and healing very well. I really wish I had bookmarked it at the time, because I can no longer find the thing.
I can still remember the basic idea however. This won't be anything near word for word but hopefully I can get the overall idea across.
Imagine yourself as a circle of light. This light is the collection of your experiences in life. As you age, gaining your daily experiences both big and small, that circle grows slowly larger.
A sudden trauma, like death, casts a big shadow onto that circle. It darkens the light, blocking it from shining over a circle of its own. Now if you are young, or if you have had relatively fewer experiences of life, yourcircle of light is naturally smaller. So, one of these shadows can feel dauntingly large leaving only a sliver of light left if any at all... while much older, more experienced people might have a larger circle fed by many other moments and memories. Enough that this shadow, though still large, is not so overwhelming. Not because the shadow is smaller but because the light is bigger. The more experienced person has tools to draw on. Happy memories to lean on. Things that are light and supporting that surround the shadow and make it feel smaller in comparison.
But for the younger, smaller circle there might not be so much light left. Leaving few positive things that can be light outside of the shadow. Some so overwhelmed that they need to share in the light of another. They need to be reminded of good memories and moral, uplifting lessons. They rely on another light being added to their own. It doesn't shine over/override the shadow, but it does expand their light so it can shine out around it and be seen.
Also, the shadow does not shrink. It is there, and unless there is an equally powerful upliftment then it will remain. Trauma is still trauma. Grief is still grief. But. The critical thing to understand is that while this shadow might not change, the light does. Time does not close the shadow, it expands the light. New Joy's, new loves, new learnings. With time, as the light grows the shadow has less influence. The light becomes too large for it to cover. And, eventually, the shadow that felt once overwhelming becomes small by comparison.
The take-away from this analogy is that no one can remove the grief and sadness of another person. What you -can- do, is help the person gain light, until it grows beyond the reach of the shadow cast over it.
The weight we carry in life does not get lighter. But we do grow stronger.