I have never experienced bereavement

I would seek support if you feel you need it OP - but not to feel guilt if you are surviving and thriving, and if you can remember them mainly with fondness, that's fab. We're all only passing through.
I grieved for my beautiful grandmother in her 90s , my fabulous aunt in her late 80s, two good friend in their 50s one from cancer and one from a heart attack. But it was manageable.
And several other losses - it's been overwhelming in a short space of time.
But the loss of a child or young person, as we have sadly known recently, is another thing altogether and can end up with trauma, depending on circumstances, which can be traumatic, horrific. It can be sudden - car accidents, suicide, other accidents such as a drowning, or an unexpected illness or medical negligence. Or 'expected' as with failure in treatment for a brain tumour (our friend's child) or long term condition - it is equally horrific , to see the deterioration in someone who was healthy and fit not so long ago.
The main thing is to be there to support others /colleagues/friends who perhaps know grief too well - to allow space, to not minimise their loss, to not lead with 'toxic positivity' ('the sun is shining, hope that helps...' - No, it will not 'help' especially if it's a traumatic loss and if it's a younger person)!. One of the hardest thing is to be told to get over it or to have someone declare flippantly 'RIP' regarding a young person. No.
RIP is more fitting for an older person. RIP is hard to hear when young people should be dancing and living their lives.
Our neural pathways change when you suffer a traumatic loss - ie it can become physical - and can cause heart rhythm problems even - but if others haven't known that, then it's not their fault that they cannot understand.