This, for example, is why people take photographs every day and now with our mobile phones. It is to be able to remember and never forget.
I know, as I get older, there are memories which would have have been long forgotten or would have faded, but with photographs, I hold these memories dear and can remember them as if they were yesterday.
So by having mementos and symbolism in our lives, it enables us to have something precious to hold onto, so when our memories do start to fade, we can remind ourselves of the important things in our past. Such as we do with photographs, but for me, I also use jewellery.
I have a beautiful locket necklace with five little crystals which symbolise the babies I have lost. The crystals provide me with something tangible that I can keep with me every day enabling me to never ever forget them.