I've noticed that painful memories seem to last longer than happy ones. They are stronger in my thoughts and dreams. So when my mind wanders, whether asleep or awake, it often comes across a painful memory which makes me angry or anxious. And yet very rarely does my mind wander across a happy memory. It is in fact very easy to forget happy moments and very difficult to forget moments of suffering. Even if I try to think of a happy memory and find one, it does not have the same emotional impact as thinking of a painful memory.
Is this true for everyone, what is the cause of this problem, and what would the Buddha have said about it? Why does the mind seem to collect painful memories and disregard happy ones?
Even if I consciously try to stop dwelling on painful memories -- there are quite a lot of them -- even if I think, "There is no past or future, only the present," or "There is no self. So, this memory is not of me, but is simply like a dream," it does not go away or only goes away temporarily; it feels like a physical sensation.
The best things in life aren't things.