(I've been struggling with this for more than a year so I'm going to try to "think-out-loud" about it here. If I step over any lines someone should yell at me.)
I will call this friend Jo, though that isn't her first name or what she goes by.
Jo and I were best friends our whole lives. I can't exactly place when this friendship really broke off. Maybe fall 2006 or right after I joined MH.
When we were babies she sucked on my head. This obviously means that she liked me. Right? 
As we grew up our families went on camping trips together. We shared many a silly song and game around the campfire. She was the one I would walk down the beach with, and when we first arrived at the beach we would race each other to the water and dive in. (I usually lost, though I wouldn't admit it at the time)
When I visited her house we would catch toads, name them, love them, and set them free. Or we would build little grass huts for stick dolls. Her yard always had longer grass than mine because my Mom was/is obsessed with mowing the lawn. Sometimes we would go exploring. We all really believed that certain sandy patches of soil were quick sand. There was a large fallen tree over a patch of Lilly of the Valley. (These flowers were often gathered and put in little vases under the icon of the Virgin Mary in their living room.) We would use the tree as our wolf den. Erik would participate in the wolf game on occasion, while Jo's older brother played the hunter or something like that. Sometimes we were all indians! Oh their poor neighbors... When we were feeling more docile there were always Beanie Babies! We would find the poor dears where they had been stranded in the wilderness and nurse them back to health. When inside we spent hours dressing up as "crazy ladies" and "Mrs. Piggle Wiggle". Mrs. Piggle Wiggle would critisize our bed making skills and the way we organized nick-knacks on the shelves.
At my house we played many other variations of the Beanie Baby game. My favorite was when the dog catcher would come and steal them and we got to free them by breaking locks/figuring out the combinations. When our Dad dug out the basement (By hand mind you!... ) there was a fantastic dirt pile in the back yard so we would go sledding on it! We built gigantic castles (or so they seemed at the time). At one point we had a really cool puddle where we could attempt to transplant pond plants and frogs. When that didn't work we would use it as the built-in mud hole so we could play spa! Yay! Aside from dirt there was lots of sticks, bark, and vines. We made countless secret forts intending all the while to play war. (We never got to the the wars...) For a year or so there was an abundance of swinging vines because Dad went through the woods and cut them all at the ground so they would die. We had a wonderful time trying to break our necks. When there weren't vines we always had the see-saw log. *sigh*
In more recent years we counted all the different kinds of fungus we could find. The only thing more fun than that was sitting on the log in the middle of the pond and looking for the critters therein. Leeches were the best discovery we ever made. It's so very thrilling to wait for hours and then scream when you finally see one. I spent several birthdays that way.
This was all a blast... But Jo is Roman Catholic and I'm Lutheran (duh). This was never a problem untill I joined MH. You see... I started talking with a lot of Lutherans, and I started acting more Lutheran. I listened to Country Music, and I started wearing flared jeans that fit! This all may seem very silly but they were actual issues. I was blissfully oblivious to any changes in Jo's behavior for quite a while. I think I got the first vibes on one of our camping trips. I won't go into details.
Long story short: Now I get along better with her older brother than with her! "Older Brother" and I are supposed to be sworn enemies. Oops. When he comes over to hang out with Erik he always sticks his head in my door and says "hi" with a big grin on his face. Last time Jo was here she didn't even ask if I was at home. It would seem that we aren't compatible beyond Beanie Babies and mud.
Quite a few of the heirlooms in my room are heirlooms because they have to do with my relationship with Jo. I have an instinct to get a box and pack them all up. Is that just silly? I'm inclined to think it is. Pasto' might say that I should keep them because those were times I enjoyed with Jo. I doubt I'll get rid of them now but I don't think that I'll keep them forever either. It seems to me that I should let go just a leetle bit.
Hmm... There's a ton more that I could say, but I don't want to think about it too hard... 
Something that has helped me alot in this situation (besides talking to Pastor Stuckwisch) is Pastor Borghardt's article on Forgiving the Unforgivables. It felt like he had been reading my thoughts or something creepy like that. What's especially sad for me is that Jo wasn't an enemy she was my BEST FRIEND and I feel dreadful about getting so upset with her. I could try to figure out what a real best friend would be but I don't have the brain power right now.
Oh and "Older Brother" now listens to Country. I hear that Jo hates it. That's rather telling. I think Older Brother deserves a Random CD for that.
I am disposed to ask, what are the chances of Jo or Older Brother or any of their family members reading this blog?
I have personally run into a direct analogy of your proposed Jo box, or box of heirlooms as it were, and I advise you to make the box if feel inclined... but put it someplace safe. You will regret throwing it away.
Though I can't *know* how you feel fully, I can relate to a certain extent. Snap and I once had some very good friends who were baptist homeschoolers. We also did everything together. We begged our mothers on our knees to let us have a sleepover pretty much every time we saw each other. Together we created elaborate fantasies and shared our most secret secrets. We even fought over doctrine like baptism and still stayed close friends.
But suddenly something changed. I still can't figure out what it was. When we were about 12years old, bang! everthing was different. These girls stopped talking to us, wouldn't even look at us when we walked past. When we try to start a conversation it is as if they have never met us before. I guess we just aren't cool enough; we don't buy the latest styles, dye our hair, paint our nails - I'm not even sure what else we don't do that makes us "out".
It truly hurts, but I still cherish the memories of the fun we shared when we were younger. I remember them as they were - not as they are.
I guess if I were in your place I would still keep your heirlooms. They were a significant part of your life and your heart even if situations have changed.
And yes....Pastor Borghardt has this uncanny quality of seeming to speak directly to the things that are bothering me. It is somewhat startling.
By the way, just for the record, I am TERRIBLY SORRY I didn't read your blog yesterday and wednesday. I am on my knees in repentance and contrition under loads of sackcloth and ashes. I begged Erik to intercede for me - I hope he did. I crave your pardon for this offense....
