No joke, I opened this thread to comment on it last night and forgot until I saw it in my feed again today.
I started keeping a diary, and I found that helps. Something about writing things down helps encode memories, but then if you do forget you have a reminder.
In particular my gratitude journal is helpful. I often find myself in a state where I can't think of a single good thing going on in my life. But then going through it I read about how a stray cat came to sit in my lap in the garden, and while I didn't remember that before I read it the memories come flooding back.