The main character in the movie Croupier has a really great philosophy: "Hang on tightly, let go lightly." It took me longer to wrap my head around, but ultimately I realized it's a rephrasing of a core stoicism concept, and I love especially memorable quotes like this.

You have ultimately no control over events. A loved one could be struck by a fatal aneurysm tomorrow and you could't prevent it. All you can do is cherish what you have, always knowing that you could lose it at any moment.

It's easy to read Epictitus and hear, "don't care about your wife, because she is already dead,” and I think Epictitus really was kind of a dick. Aurelius was either a better or not compassionate author, though, and phrased it around cultivating an awareness that we are powerless against much of the universe, so hang on tightly to what you have, while you have it, but let go lightly when it is time, and don't carry unnecessary grief and things you can't control.

Stoicism seems, to me, to focus much on answering your specific question.

Yes?

Rage against the dying of the light, always. But sooner or later the end will come for us all, and that’s the part that’s the hardest to accept on an individual level, in my opinion. I still get the occasional existential crisis.

Instead, be glad that you’re here now and do what you can to make the world better for yourself, your neighbors, and society as a whole while you are. That’s all any of us can hope to do. Leave it a little nicer than we found it.

I honestly don't think letting go implies giving anything up! I see it as letting go of the emotional load of some memories, but not of the memories themselves. I still choose to remember everything which happened to me, because it's my past and I can do what I want with it, I just don't let them burden me with emotions past their Best Before date (which is nonsense in practical terms, but I'm using it metaphorically).

Plus letting go of old things makes room for new things, like how one will never appreciate a current partner if they're hung up on an ex. I see the same thing applying to everything else, including humanity ourselves! Gotta let go of the old in order to make room for the new.

When the angel of death comes.
I won't cry.

I won't weep and wallow 
"Oh why, why, why"

I won't bob and weave 
When he swings his scythe 

I'll look that fucker right in the eye.

You come for me?
G'wan then, give it a try

I'll go down swinging 
When it's my time to die

God is change. All that we touch we change. All that we change, changes us. - Earth Seed, Book of the living - Parable of The Sower by Octavia Butler

As someone with cptsd letting go isn't an option and death is pain relief.

Yes