There are times I've wished I've journaled to at least some degree so as to give me perspective. Memories can be funny, malleable things.
My son has started an online journal, it is called Day One, and there is an app for it. He has the premium version, and I just got the free one. I am writing old family stories as I remember them, and eventually, he is going to merge them with his so that other people in the family can also read the stories. I think that saving these old family memories is a good thing.. Like most girls, I had a diary when I was a teenager, and have tried a few times since then, but just am not motivated to write down all of my thoughts anymore, except for telling the stories for my family.
My mother lived through WW2 in London as a late teen/young adult, and a couple of older siblings tried to get her to do that, to no avail. I have no idea if she did not want to relive bad memories or if she just had no interest.