I have usually had 2 diaries for most years in my life from when I was a young teenager. The mundane one was the one with appointments and dates to remember and birthdays etc etc. The more private one was for my eyes only , and reading through them occasionally over the years, has reminded me of forgotten days good and bad.
I was quite good at sort of setting the scene on occasion, and sometimes read an extract that takes me back to the sounds and smells and feelings of a particular occasion. How I felt, the special or dreaded anticipation of something, what I had to eat , who else was there. I seem to have quite good recall generally, not something that I am always pleased about , as can get the awful feelings that I had on certain occasions. Never able to forget the moment I was told that my granny was killed in a car crash , when I have a sort of frozen total recall of sounds, smells, what I was wearing everything. But also have the wonderful total recall of standing in a garden in the summer evening with a light breeze, can picturewhat I was wearing, the smell of lavender, and mint and that sort of cool smell after a very hot day. So my diaries are there to check times and things out and to sometimes bring lovely days spent with my husband to mind.
I used to write long letters to my mother for the two years I lived in portugal, which not only had family matters in them but also feasts and occasions that I saw and these were all kept and are now in a museum, as they give a sense of life in Portugal at that time. So despite all the internet etc I think there is something special about diaries kept over long period, and I have lived my life to the best I could, making mistakes and doing all sorts of things over the years, and I dont intend to destroy them. Rather I leave it up to my son or whoever to read what they want and do as they like with them. It wont worry me by then, but they might be interested in some of my goings on , and I dont care if they get a few shocks and surprises, as I wasnt always an old lady, and I will be glad that they will be reminded that I did live a life, as they are now doing.