Babieseverywhere Good luck! Hope you have lots of strength and progress today.
Solo ”I'm doing it” Those are the magic words. It doesn’t matter what size big or small, It is the doing it that will get you and all of us there. 
TBH I only scan read part of the other threads because they make me recoil and slow down me making rational decisions about individual items here.
I need to do a lot of work on myself before I’m able to deal with a lot of stuff to do with my children. I doubt my Dc will want their 18th birthday cards, or the cards they made as toddlers in the future but they like me having them at the moment.
They remind me of what was good, and I need it, both to offset my past, and the ASD tendencies of those I love deciding that their whole lives where always whatever today's situation happens to be which I understand, but rather gets me at times.
Me being was a bit of an awkward thing, but I'm unsure why exactly.
It was certainly never a cause for celebrations or cards or photos, and absolutely all evidence of my childhood and teenage years was wiped away by others, often as fast as possible. In some ways it's good as less stuff, in other ways it's not.
My birthday was always awkward because siblings birthdays were celebrated but mine just quietly wasn't. I knew it was there, as we all did, but it was expected that everyone should act like there was nothing different about the day
but no one ever said why, but it seemed like I was supposed to know.
But, on my 10th I was unexpectedly brought a cake but without candles, (yep, scarcity didn't equal total gratitude!) then it was back to silent expectation that nothing should be mentioned.
After my mother died relatives did the same thing, so clearly there was something wrong with my birthday being noted and I suppose I internalized it
I wanted my children to have 'normal' and feel different. I’ve succeeded, but their cards, creations, and photo's probably mean more than they should to me. I haven't kept absolutely everything, but a fair bit! Plenty of other things I'd rather let go off if I have to choose.
I love your idea, and may pitch the idea to the kids of having it all buried or cremated with me. 